I am going to chime in and call bullshit! I was on the Wyoming state swim team when I was in middle school and High school. I competed all over the state against all ranges of ability. My coach wasn't happy when I moved away because I was one of the teams top swimmers for my age group. I won a lot, and I lost a lot. There where girls on my team, who could beat me hands down. Now I know that doesn't mean much to you. But here is the part that disproves your theory: The best swimmer on our team, who took home many state titles, had only 1 lung. he also could hold his breath longer than anyone on the team. If what you say is true, because he was born with that disadvantage, it was impossible for him to do any of that. Sports when it comes to the body, is more about conditioning ones body and mind, than anything else.
Now, to everyone: If allowing and not allowing transgendered people is such a huge deal, than why do we allow black people and white people to compete with each other as blacks tend to have a greater athletic ability in some sports? By no means am I making this a racial discussion, as that's not why I bring it up. But genetics play a huge roll in athletic ability, are we going to start separating people based on genetics as well because some genetics have an advantage? Are people going to start blaming their losses due to their lack of conditioning because of genetics? Most sports are designed to match people at the same level, that won't change if trans athletes enter the picture, it will just take a little time for the averages to work themselves out where the matches are balanced appropriately. At least that is how I look at it.