While "neat", I don't find it very reliable. According to the comments (and how the "wrestler" threw himself backwards), it was just a very fancy demonstration.
I take issue with that comment about the wrestler throwing himself backwards.
The alleged incident is probably referring to 0.50 in the video, take a look for yourself and see if you agree with the comment.
For me the comment is obviously wrong due to 3 main reasons:
1) The wrestler was thrown backwards like a ragdoll, if you threw yourself backwards you wouldn't be able to replicate the ragdoll quality and the dynamics of the fall would look very different overall. To fall backwards as he did in the video, there would have to be a significant external force.
2) To non Tai Chi practitioners, it would seem like there was little in the way of any real strike that would have resulted in such a dramatic fall, but to us Tai Chi nuts the move was very obviously a 'Kao'. The thing with 'Internal' MA's like Tai Chi is not that we use some mysterious energy to throw chi balls and such (although for some reason that is still an oddly popular misconception), but that the focus and intricacies of our MA is not apparent externally, but the effect is often disproportionate to the move.
EDIT: just to add.. there is a lot more going on during the session that meets the eye, if you get in a clinch with an accomplished Tai Chi player you will immediately feel that your balance is taken from you, there would be a lot of back and forth between the 2 of them even without externally visible moves being attempted.
3) There are many videos of the person (Chen Ziqiang) engaging in tuishou (push hands) sparring sessions on his overseas visits very much like this one. The Kao move is used on numerous occasions to similar effect.
Lastly, also to address Steve's question, the wrestler is also a Tai Chi student. They were not engaged in a demonstration but Tui Shou sparring, and as I have mentioned, there are numerous other videos of other similar tuishou sparring videos on youtube, just have a look...
I would only agree with the sentiment that labeling the video as 'Wrestling vs Tai Chi' is somewhat misleading, when in fact it is a Tai Chi student with wrestling background engaged in sparring with his Teacher who happens to be one of the best Chen Style Tai Chi exponents of his generation.