I never quite saw the point of these programmes, but this was probably a relatively good environment to be part of them in – there were a group of similarly talented youngsters in it together, so not everyone had to have a heavy role in filming. And any question of being told you are a “genius” doesn’t really apply: having been chosen for the Olympiad squad already lets people know they are somewhat special. But probably most importantly, there was an organisational structure to run the team who (at least after the first programme) had experience in dealing with programme makers and setting rules for them. I suspect that in most of the programmes you refer to, whoever initiated them, once they had begun the parents had little control over what happened.

Telling a child they are a genius is a bad idea. Telling them on a tv documentary is both tacky and disturbing.