Furthermore, the fact that Erik only works in this vid with going from some wing chun blocks, parries, and redirects (pak, bil, huen) to clinch, and some chi sao rolling motion to a fuk sao-like bicep tie...
and didn't include punching, palm strikes, and some use of block-and-strike...
doesn't mean that these aspects of wing chun can't be done against a skilled, resisting opponent. It simply means that he chose not to deal with any of that.
His focus in this vid was on something else.
Do you recall any posts of mine from previous threads (say about a year or two ago) wherein I wrote about
punching at the opponent's shoulder lines?
Now compare that idea with Erik's idea (and what he actually demos) about using his left arm to bridge into his opponent's right arm/shoulder/bicep area...and his right arm doing the same against the opponent's left...
and see how this squares with the wing chun concepts about virtually always using two arms at the same time - as in some version of simultaneous (or near simultaneous) attack and defense.
Think about it.