As a non Pilot, I would have thought there was a little more to it than that. Wouldn't just throwing a big heavy set of wheels on it unbalance the aircraft? I notice when he guns the engine when taking off from the rock, the tail just seems to lift without need of forward motion!
Remember reading a quote saying 'The Piper Cub is the safest airplane in the world; it can just barely kill you.'
I'm sure Twinotter600 can let me know if there is anything special about this particular plane, but you gotta admit, it has the ability to land and take off spectacularly, better than anything I've seen.