A completion to my earlier post
My interpretation of MMX includes a very small motion in transverse direction that can fool some people to regard the idea impossible. However, assuming the ether entrained by the Sun means that we must give the same capacity to the Earth. So, ether wind is only 10^-6 due to rotating Earth, in horizontal direction. The effect is about 10^-12. An arm length in MMX of 10 m will mean a transverse motion of only 10 micrometers, and, with a Q-value of 100, the total motion is only 1 mm. This small amount will not cause any problem for the test, since the mirrors are much larger that 1 mm.
We have therefore demolished the prejudice. The case with the swimmers may have been misleading since, in that case v/c is about 1, instead of 10^-6.
See also Fundamental Errors in Physics at www.gsjournal.net