I agree, but there are a few obvious steps backwards in round four or five, plus that's how they move forward, it's way more tail than legs. It's a slippery slope.
There was another video of an interview in the 70's with a boxing kangaroo and the lady conducting the interview was taking a beating. The 'roo must have landed 5 solid head shots while she was talking. awesome. I almost fell out of my chair.