the aerialists dont actually spin off the jump from what understand. Aerialist just throw a STRAIGHT backflip and once they start flipping they move their arms in order to INDUCE a spin because of the conservation of angular momentum. Same as when you have a gyroscope and try to turn it one way and it moves another way for some reason. They are backfliping so fast that it has alot of angular momentum so moving their arms in certain ways can get them to spin in a way. They can also do the same thing to stop themselves from spinning. That is why aerialists always seem to end their trick without spin.
Just watch the first jump in this video. He starts with only backflip, and then moves his arms to get some fake spin going.
So anyways I think dumont is nasty as anything, but his front flip to misty 7 is just a front flip aerial. He does a straight front flip and then starts himself spinning with his arms. Its cheap spin though, not real.
its at 125 in this video
So anyways i think Deschenaux was right about simons front flip misty, it really is an aerials trick which is kind of gay. Kangeroo flips are def not related to aerials i dont think.