I graduated from Carlbrook in 2008 after being there for 19 months (plus 3 months of wilderness therapy). Communication IS monitored. All incoming and outgoing letters are screened. My parents and I often didn't get each others' letters or huge hunks were edited out (we would bring up parts of the letters on phone calls only to discover that they had been mysteriously removed). Phone calls are monitored by Laura The Phone Lady as well. If you have a "tone" in your voice or say anything anti-Carlbrook, she emails your adviser and you are punished with bans/an Action Plan/suspension/taken away visits/etc. If you have any other questions, I'd be happy to answer them.
At Carlbrook, I was a golden child -- supported workshops, Head of the Friends Committee, Prefect, etc...however, after graduating and looking back, I realize how completely brainwashed I was.
Carlbrook is preferable to hellholes like Elan and Island View, but I still recognize how unnecessary and scarring some of my experiences were there. Being forced to go to my own funeral, being hit on by creepy old teachers, being viciously destroyed verbally in group for no reason (false accusations happened all the time at Carlbrook and there was no way to deny them), being convinced that I was crazy and disgusting so that they could "fix me" and show me how I wasn't (even though I never thought I was in the first place...), etc.
Carlbrook taught me the valuable lesson of how to know when to bend over and take it up the ass, honestly. Carlbrook taught me how to pick my battles and when it was best to submit and just play along. I got some good stuff out of Carlbrook (good friends, Andy Coe, etc.) but overall it screwed me up.