some of you are saying that the only way to truly "know" a teacher's skill is by touching hands with him;
on one level, I agree - there is a level of information that can only come from hands on contact;
however, there is a caveat to this, which is that having had some experience in MA, after a while one is able to correlate visual performance to hands-on skill to some degree: when you've touched hands with a lot of people, and then you see how they do their forms, you begin to establish a correlation between visual information and tactile information; eventually, you can start to extrapolate from the visual with a pretty good degree of accuracy; to wit, if someone is doing a form that displays poor mechanics, poor timing, etc., you can reasonably extrapolate as to the level of their hands on skill: no one is going to lack these things visually and then turn around and be awesome "hands on" - it just doesn't work that way...(BTW, this doesn't work the other way around though: someone can have excellent form, like a top level wushu guy, but it doesn't mean his fighting skill is any good necessarilly);
but here's my real problem with all you guys defending Doo Wai via his clips: you guys want to have your cake and eat it too: what I mean is that, if someone saw the clips and said "wow, from the looks of those clips, he must be an awesome fighter!" you wouldn't jump in and say "oh no, you can't say that - you have to touch hands with him first before you can say that"; somehow, I suspect that this would not be the case...
furthermore, if I am not mistaken, the whole point of Doo Wai posting those clips in the first place is to impress people visually: I mean, he's not posting them because he thinks they are bad clips; he's posting them because he thinks that people will see them, be impressed by them and then study his system as a result; so he is in fact asking people to make a judgement based on only the visual information; and again, as long as the opinion is a positive one, no one is jumping up and disabusing the viewer of their perspective; of course, as soon as someone makes some reasonable critique of the clips, that is, they don't just say "he loks" bad, but actually provide specifics as to why they think the form is lacking, you all jump in with your default "you have to touch hands to know for sure" argument...
you guys need to be a little more internally consistent with your arguments...