My reasons for being sent there are similar to the author's. I didn't take my dad's car without permission, but I did drink a lot, skip school, was generally rebellious and refused to be disciplined. My issues were compounded by the fact that my mom had died when I was 11 years old and my dad worked in a field that required lots of travel, so he had a lot of trouble supervising me.
The school was terrible in its methods and I don't think their therapists were qualified. Males and females were completely segregated and talking to females would get you immediately thrown into "jumpsuit", which was the harshest discipline level and meant you lost all privileges and had to wear an orange jumpsuit 24/7.
Responsibilities were doled out in a few levels: on-shadow, shadower, and appropriate. An "appropriate" was the highest level of responsibility, trusted to monitor groups and make sure nobody broke rules or talked about inappropriate topics. "Shadows" were trusted to watch other people and help the appropriates deal with new kids and misbehavers. On-shadow just meant you always had to be with someone watching you and you didn't have any of the trust given to higher levels.
You weren't allowed to go anywhere without an "appropriate" and at least one other person. Even when I would take a shower or go to the bathroom, I had to have someone watching the door and waiting for me to finish.
Parent phone calls and visits were supervised by an "appropriate" until you got to higher privilege levels and were allowed to go off-campus. This was to prevent newer kids from complaining to their parents and getting their parents to take them out of the program.
Lots of the graduates were convinced by management to stay on for their "sobriety" and help as an employee/intern with the kids and dorms. I remember several graduates who stayed 6-12 months after their graduation doing this. Seemed like a scam to me.
One guy from my class ended up marrying one of the dorm monitors, who was an older, but attractive woman in her ~30s. This seemed really odd to me, I don't remember there being any opportunities to do anything like have inappropriate relationships, but things did apparently change after I left. I heard a few months later kids were doing crazy stuff like breaking into the medicine cabinet and the males/females started hooking up. But when I was there, that kind of stuff was out of the question and unheard of.
The only music we were allowed to listen to was really old stuff like Beatles, CCR... Movies were filtered for any scenes with alcohol or drug use, no talking about modern music, movies with drug use, drug use or partying / etc. was all forbidden topics that would get you in a ton of trouble. Punishments ranged from writing 40,000 god prayers to digging ditches or cleaning for hours.
Overall, I needed some kind of wake up call, but I ended up leaving when I turned 18. They threatened that I wouldn't graduate on-time and go to college, but I had already been accepted to university and I knew that most of my credits would transfer. I finished out the year at public high school, went to college, and moved on with my life.
Edit: I'm reading through https://elan.school , and it sounds like my school copied their program, even using a lot of the same terminology "strength" vs "non-strength" etc.