Do you actually skate? I'm a skater, and I land kickflips and all that, and believe me, crouching like that does NOT look realistic. It's even more possible to skate in a straight line, trust me, I managed to ollie like that. But you need to have the most sick bendable legs ever to be able to crouch like that. Plus using Jon's flip, you can only flip for 3 frames, first flip, upside down, second flip. Seriously, if you look at the skateboard, you can notice it flipping, it's just when you're not really focusing on the flip, it seems really awkward. Sorry if I seem harsh or anything, I just know that skating crouching like that is not possible in real life, and does not look good in animating either.