has to be done pretty early to avoid the advantages...

For example, a pre-pubescent boy and girl are often VERY close physically and combined teams are normal and quite fair...

But once puberty hits, that's where the big changes start... but they don't go away completely even with hormonal treatments...

If we take a 25yr old male athlete and a 25yr old female athlete, we know there are going to be some marked muscular differences. But the hard part is that even if we castrate the male and drop his testosterone levels to match hers, he will actually still RETAIN some of those physical advantages that the male hormones gave him over the last decade.

I don't even PRETEND to know how to solve this one. IMO my GUT is to simply stay with genetics in the SPECIFIC realm of competitive athletics. XX's and XY's compete separately. Yes there will be a FEW XY's who will be unhappy because they can't compete with the XX's they feel like and a few XX's who will be unhappy because they can't compete with the XY's they feel like... But I don't think there is another GOOD way.