So which approach is most fair? “Fair is a very subjective word,” says Joanna Harper, a transgender woman, distance runner, and researcher who served on the IOC committee that developed that organization’s current rules. It boils down to whom you’re trying to be fair to, Harper says. “To billions of typical women who cannot compete with men at high levels of sport?” Or “a very repressed minority in transgender people who only want to enjoy the same things that everybody else does, including participation in sports?”
I genuinely don't know which side of the argument this quote is trying to prove 
Why should the billions of typical women lose the opportunity to be successful at women's sport so that it can be seen as 'fair' to a small number of transwomen, who would be mediocre in men's sport but who head straight to the top of women's sport? That's not a fair sporting achievement for the transwomen. If it was about fairness, they'd want to compete only against other transwomen. It's not about fairness though is it - it's yet again about autogrlynaephile's need to have everybody affirm to them that the emperor does indeed have clothes.