So on the AiB joke ladder, I've been going my secondaries just to see how they do (MK, ICs, and Jigglypuff). It turns out most people in general don't know how to beat MK. When I lose, it's usually because I kill myself, or they get extremely lucky. People generally don't know the matchup.
I've played a couple of Peaches, too, with MK, and I'm actually surprised at how easy the matchup is. Either my MK is good (which it isn't) or people don't know how to beat MK. They float a lot, which allows me to tornado them, and they don't really camp.....
I now see why Peach has so much trouble with MK.