Good luck to you / your son!....our experience is a lot of success has to do with the experience, and technique the Dr. uses....IMO there is a big difference from an ortho that "can" do it, versus to a guy that does many, many every year. Once the surgeon / surgery is a success, it's all about the rehab process, and which route you take. My son skipped (gap year) his Frosh year of college, and instead spent the equivalent of a Fall / Spring semester at Driveline Baseball (Seattle area) to rehab, then train, and then back to throwing....was a daily grind, but he loved it. This was his first time away from home (live in Texas), and he had to grow up quick. He is not quite 18 months post TJ, and now throwing in college, however just recently had another (hopefully) small set back, which is par for the course up until about the 24 month mark.
Mentally it can be challenging for some depending on the mental make-up of the young man...it is a lonely, sometimes grueling process, where at times you don't think you are making any progress at all..lots of plateaus, and for some set-backs along the way....however it is very doable.