But that's not really realistic either. Anyone who's good at tumbling can flip, somersault and roll without losing their spacial sense (and in fact from what I've heard it helps to focus on a stationary point of reference). This is largely how trapeze artists can flip through the air and still catch the next swing bar - they are tracking it in motion. a madly swinging camera POV does not account for a human's ability to move their head and eyes to keep their target in view through 80% of the maneuver.