How would you separate 2 swimmers (one trans,
& one cis) capable of different significantly different
times in a race? (The trans is faster.)
I'm not a swimmer and this is just a suggestion so I am certainly not claiming to have all the answers, but I'd suggest where appropriate, separating swimmers by average of swim times and perhaps other metrics that show skill levels.
Next question...
What if 2 swimmers have nearly identical performance,
but the trans female swimmer wins repeatedly?
Then the swimmer winning repeatedly is the superior swimmer. When you compete, someone loses. I imagine athletes don't just compete to win, though, but to improve their own performance and for the spirit of the sport.
Do you think cis women would be satisfied with
their accomplishments under your system?
I think it depends on the athlete. Some people compete due to their love of the sport. Some for pushing themselves into better performance. Some are driven by competition.
Finally, why not have totally separate events
for cis & trans women (as others have suggested)?
I am sure this would likely occur anyway, since division by gender has been the thing for a while. Even with professional competitions divided by skill levels, I can see there being other leagues that focus on other things like gender.
But why not focus on skills rather than gender? After all, if we are competing to define skill, why not offer competition that allows for genders to compete together?
This may also show the potential of females to be able to compete with men. If there are physical differences that training cannot compensate for, the skill levels will show this anway. If training can compensate for the given sport, then men will have to deal with women beating them sometimes.