The Fair
IS auto-lag cancellable. You just have to jump, dj-a really fast. I just hit y with the tip of my thumb and then flatten it onto the A button almost at the same time. It's kind of hard, but gets easier and easier as you try it out, and man is it scary looking ^_^. As far as uses, I can only see it being viable in teams, 1vs1 at low percents, or as a mindgame.
The Nair is auto lag cancellable just by full jumping, and then the bair/uair auto lag cancel regardless. On the subject of the bair, someone mentioned they couldn't hit short characters with it; you can, you just have to delay it almost as you would a ground-based uair in melee. It doesn't have any more sex-kick properties
.
On the topic of Bunny Stomping/Thunder Storm, are you guys saying you can
short hop dair and have it auto lag cancel?? I haven't been able to do that, but then again I didn't try because I could already full jump auto lag cancel it easily and that suited my purposes well enough.. but if I can short hop it..... Ganon is officially broken o.O.