Ah, OK. I'm thinking along the lines of some experiment done by Robert Winston - Child of Our Time. He looks at kids as they grow up, from the day of their birth till I don't know when. Quite interesting - he's being doing it for years.

The way Robert Winston does it is probably very time and money consuming, your way would be quick and less expensive.

But then, what happens if in your Population you get a child who has had a very traumatic experience, that, in later life, may lead to 'being gay'? How would that be taken into account?