Andy- hate to be "that guy", but this clip doesn't prove a darned thing.
You posted it earlier as well, and as someone else already pointed out there is so much motion going on that you wouldn't be able to spot a clean key versus a messy one in the first place. Not to mention it has been down sized to 480p. I mean, any HD camera downsized to 480p will work according to my explanation above about resampling. I'd say you could have probably shot this on an iPhone4 and gotten roughly the same results.
