I half suspect it's intentional manipulation of public perception, like that one MtF lifter in the Olympics who supposedly stuffed his lift on purpose to "prove" that he (and, by extension, other MtF cheaters) didn't have an advantage over real women.

Get someone MtF out there, have them put on a sloppy-ass performance, and obviously that demonstrates that they're competing on the same level. Then the next one comes through and utterly shatters the event, but they're clearly not doing so on the physiological advantages of being man, because so-and-so's performance earlier demonstrates that MtF don't have any such advantage, right?