I've told my 
story
 (Attacks on ATRs is Spear at All Teachers Plus Why Not Have a Permanent Corps of ATR) of being an ATR in my first year and a half as a teacher from Sept. 
1967-Feb. 1969 -- an experience that I believe turned me from a 
no-nothing 6-week summer trainee -- ala TFA -- into a confident teacher. So I found this email from Ed Notes reader Nick Weber confirms my thesis that using a permanent ATR corp for beginning teachers as a sort of apprenticeship would make sense --  also cost so much less because it would consist of beginning teachers -- we need subs anyway so why not make use of them but add the mission that schools they are attached to would also function like teaching hospitals? Re-branding the ATR program in this way would lead to buy in -- having extra hands on deck in schools can never hurt.
Here is Nick's intro:
As one of the youngest ATR's in the city (30) I have been an ATR  for the past three years, and have been reading the accounts from  "journalists" that fail to even ask an ATR their take on the process.  While I note the difficulties inherent with not being given a restroom  key, unfair evaluation, and being treated by some as a second class  citizen; this is not the totality of my experience. 
As  the old adage goes, when life throws us lemons...  In light of this  sentiment, below you will find my positive take on the experience, and  the positive experiences I have been able to collect from it.  It has provided me one of the most unexpected life  experiences, and one that has enriched me as a professional and person.    I humbly offer the following account below, in the hopes that you may  publish it with my name, so that we may turn the tide on the  representation of what is a cadre of highly trained and brilliant  professionals, enriching schools across our City in wonderful ways. 
----ATR Nick Weber
I can imagine the storm this posting will incur from a certain segment of the besieged ATR community. Nick is 30 years old and has a long way to go in the system so he has a perspective that may differ from long-time teachers. I do want to echo some of the points he makes about being able to visit many other classrooms as opposed to the isolating experience when you are a "normal" teacher. We know from some prominent ATRS - Eterno, Portelos, Zucker that they have managed to handle things pretty well -- James is the only one who has had a stable situation - relatively.
The press doing reporting on ATRs might want to chat with Nick and get his perspective.  
A first-person account of an ATR teacher in New York City Public Schools 
The Traveling Teacher
It  is a rare and select opportunity for an educator to receive an  invitation to visit another classroom within their own school site, let  alone a chance to visit over three dozen school sites as a faculty  member of each community.  In spite of the rarity, my assignment for the  past three years within the Department of Education has been to do just  this:  teach students in classrooms across schools, grade levels, and  content areas.  It has been an unexpected blessing that provided me an  opportunity to grow in unique ways I never imagined possible. To help  populations of students I never imagined that I would work with, and  learn from dozens of professionals who, in total, have several millennia  of classroom years of experience. This account of my experience has to  be abridged in order to present some of the insights of my time as an  ATR.  It is an account that reveals, a side of being an ATR which has  been beneficial to increasing my teaching ability and practice. 
The  assignment of schools for ATR teachers remains a veiled calculus that  is beyond analysis.  For our purposes, ATR teachers are sent into  literally any DOE institution and regardless of their licensure and work  to “cover” any topic or grade level.  My personal experience teaching  as an ATR ranges from Pre-K all the way through senior year. A  non-exhaustive list of content domains I have taught are as follows;  Algebra, Geometry, Calculus, Chemistry, American History, Global  History, Art, Design, Physics, Spanish, Latin, American-American  Literature, American Literature, Theater, Music, Economics, Physical  Education, Business Marketing, Coding, and library sciences.  This  constant rotation has afforded me insight into how students learn,  across content areas, and among the most diverse student population in  the world. It has granted me the opportunity to peer into diverse school  communities and learn how they function from my interactions with  principals, assistant principals, teacher leaders, teachers, students,  food service workers, School Safety Agents, and custodial staffs.  With  reflection, these experiences have enabled me to understand public  education in New York City as an ingrained member of a school community,  with teaching obligations parallel to fellow educators, yet under a  rotating set of conditions.  
Switching both  the school and classroom setting permits an amazing level of  professional growth, should one engage in the teaching process with  fidelity.  My experience being an ATR was to treat every classroom, as  my classroom.  Every lesson, as if I had weeks to craft it, not merely  hours.  Every student, as my student.  
Working  with over seven thousand students and hundreds of colleagues, it is a  rare day that goes by when I don’t run into someone who I taught or  worked with over the past few years. Sharing a smile and pleasant  conversation to catch up with them, has been a true blessing of this  constant rotation.  Updates abound with their college success, career  growth, entrepreneurial endeavors, volunteering, military service, and  persistent growth and learning, among a cadre of students who face no  shortage of adversity against them.  The more students I teach and  professionals I work with -- the more I discover that the human  condition is categorically similar.  When we invest with kindness,  support, and care for a generation; the result is a success all around. 
ATR  teachers are often considered merely substitutes. This is an  unfortunate understanding,  and should the ATR view themselves as such,  would result in a self-fulfilling prophecy.  The facts are less  glamorous than sensationalist accounts.  In contrast to the experience  of being a substitute, the average ATR teacher has years, even decades  of experience.  Hence, divergent from a substitute walking into a  classroom, ATR educators are full-fledged teachers, who understand  classroom dynamics, pedagogy, learning theory, and evaluation.  
That is  to say, ATR teachers who constantly strive to perfect their teaching  methods and reflect on every lesson, are able to experience an enormous  amount of growth within a framework where change is the rule, rather  than the exception.  With every class and student I teach, I reflect on  what aspects of the lesson were successful, and what aspects of the  lesson should be altered next time for improvement?  Research and our  own personal experiences reveal that when teachers remain static, their  lessons slowly ossify, and student interest decreases. Any pedagogue  will acknowledge, that decreased student engagement results in lower  student learning.  Teachers who remain, avid learners, are the ones who  meet the greatest success. 
Within the United  States, the current method of teacher preparation frequently  compartmentalizes teacher training into both grade and subject-level  specializations.  Frequently, this specialization comes at a cost of  understanding the continuity of learning from pre-K to grade 12. While  it is imperative to prepare teachers to understand the content and  pedagogy with respect to subject domain (i.e. Middle School math, high  school Chemistry; grade level 12 Economics), the process of teacher  preparation may serve to isolate the teacher beyond what is needed or  beneficial.  Teachers must be able to understand how learning occurs,  and see the connections across grade level, student populations and  understand barriers to learning. 
Evidence of  hyper-specialization within education abounds. Teachers often identify  strongly as history teachers, math teachers, and science teachers.  Yet,  does not every subject impact another?  Should teachers (and  administrators) not understand how students learn across content areas?  Are not the most brilliant discoveries often found by researchers  working outside their field of direct experience?  If so, we must  expressly ensure teachers see connections, strategies, and methods  across content areas. 
The world of today  places great emphasis and opportunity on students who can see  connections across domains and specializations. Our economy values  individuals who have diverse skill-sets, and are able to reach across  specializations. Innovation demands that we prepare students to create,  rather than solely to perform within a limited task range. Thus, our  teacher preparation must reflect this. 
Preparing  an English teacher to teach High School, results in teachers who  encounter challenges with supporting who enter high school reading at  the 6th-grade level.  Alternatively, middle school math teachers, may  not understand the rigors of Algebra on the 9th-grade level and thus  fail to prepare a continuity of instruction for their pupils to engage  with instruction on the high school level.  This is not a fault of the  teacher, but rather a system of teacher preparation that focuses on a  single subject and grade level.  I title hyper-focused content area  specialization,  ‘silos of instruction’. These silos, unfortunately,  carry all the way through teacher preparation and are maintained within  many schools.  My integration into around three dozen school  communities, permit me to see the inefficiency many schools experience  with single subject content area teams.  An example of this is when high  school math departments, fail to realize many of their English language  students perform poorly on state math exams as a product of language  deficits, rather than mathematic difficulties.  A partnership between  these departments could address such concerns.  
Teaching  across student populations and content domains,  aided my ability to  view how student psychological, social, and academic development  occurs.  In contrast to remaining with solely one student population,  being an ATR grants insight into how students acquire knowledge at all  grade levels of the public school. The ATR teacher, given their  expansive placement with regard to grade and content domain; has the  opportunity to see not only grade level benchmarks but additionally  content area connections.  They have the chance to see the connections  between literature on the elementary level, and mathematics benchmarks  on the tenth grade.  No other teaching opportunity within our City or  nation provides this diversity of applied growth and learning for  teachers.  For rather than being an observer there to 'evaluate'  learning, ATR teachers are in the classroom as a co-constructor of  knowledge.  For example, I have witnessed how deficiencies regarding  reading, translate as barriers to understanding math concepts when  instructed and evaluated with a high degree of written instructions.   Using the tools  I have gained while teaching both concurrently,  has  helped me to facilitate student learning to address these challenges. 
Teaching  methods are critical to engaging students in the learning process.  One  of the benefits of ATR rotation is the chance to acquire new "tools" or  teaching methods.  Working with around 70 co-teachers (classrooms with  both a special education and general education teacher in the room) I  have had the chance to acquire a host of teaching strategies. One of my  favorite teaching growth activities is to adapt and implement strategies  in unconventional manners to increase student learning.  Take for  example my use of "foldables" (a  project most often associated with  English Language Arts methods) to increase Algebra passing rates.  Along  with a co-teacher, we planned lessons using these manipulatives and  found that students increased their pass rate of the state Regents Exams  to one of the highest in the school.  The process of working with so  many different and amazingly talented educators in the City, has been  one of true joy and a professional honor.  Viewing how teachers adapt to  students, integrate their interests and needs into the lessons they  teach, and passionately support students far beyond the scope of their  duties, reveals the level of professional dedication of so many  teachers.  While the role of ATR is particularly suited to working with  diverse professionals across content areas, I encourage regularly  assigned teachers to simply ask around their school to find amazing  educators, and engage in peer observation with fellow teachers. 
ATR  assignments to school communities for myself have ranged from a single  week to around eight months in duration.  Within so many school  communities, I have discovered that the school climate and culture may  be radically divergent. The diversity of school environment is something  to be encouraged.  For example, students at Art and Design High School  in Manhattan often express their creativity via sketches and artwork  they draw in their portfolio notebooks, purchased in the school store  which sells them to students at cost.  In contrast, schools such as  Grammercy Arts, focus their artistic expression most profoundly through  theater arts such as drama and dance.  To comparatively evaluate the  “quality” of such radically different environments, using the same  basis, is a fool’s errand.  Success in the classroom is similar to  success in real life, it simply looks different for everyone.  Different  populations of students with unique needs and teachers with unique  skill-sets are invariably different. Society must come to embrace the  diversity of excellence, and how it manifests across schools. 
Successful  schools tailor their course and extracurricular offerings to match the  student and staff interests and abilities.  Student interest is a  critical ingredient for school success.  Being an ATR has allowed me to  witness how the same student, engages in learning across different  content areas and classes. That is to say, a student who thrives in  group work in a History class, may be reserved and quiet in a science  class.  Discovering indeed that a particular student learns best through  group activities, may be a critical piece of information that educators  fail to notice with some students. Why would they not? Indeed the  single content area focus, as well as departments based on subject area,  often place barriers in terms of teacher's  knowledge of students.  Exploring how an individual student learns, is a critical feature of  student success, and one that must be understood by members across of a  school community. In an ATR role, it becomes apparent that every student  has learning preferences, and these must be understood to best support  student learning on a student-by-student level. 
Overall,  rather than viewing the ATR experience as one of diminished responsibly  and growth, I have engaged these past years in this role in a manner  which illuminated me to the experience of learning within the public  schools of New York City.  Teaching in a plethora of schools, across  grade levels, across content domains, and with some of the finest  educators to wonderful students who strive forward each day in spite of  the many obstacles, has been one of the most enriching teaching  experiences I could have ever imagined. 
- Nick Weber, ATR