There are plenty of sellouts in any program. Normally they stop after leaving the program though...
It lasts a while for some, and if, as WWASP suggests, parents help to help kids "internalize" the program's change, the change can be more or less permanent... At least while there are supports in place for his belief structure (easy when working in the industry, or living with controlling parent(desperate for parental approval / affection / love))