Ok " The Real Deal" what is it?..Well you can use a screwdriver to open a tin of paint, is that what a screwdriver was designed for?
You design something with a function and a purpose, now it may not deliver that purpose and require tweeking, but it still has that purpose. If you change the purpose then you need to change everything.
Now ask yourself what is Chi sao? basically your arms are in a blocking position. The tan sau is very strong as a block, but if you push it really hard then you have to roll the arm ,and it becomes a bong sau, which is also very strong if you understand it's purpose. so the purpose of the exercise is to execute a block against a strong opponent and see where that takes you when it changes, or how you can gain an advantage.
It is important therefore to retain some semblence of a block, the stance is also important in Wing Chun, as the stance is tied or related very strongly to the arm position.
If you are out of stance, if your arms are not in a blocking position then you have changed the purpose of the chi sao, it has become something different..and that is what this guy has done. Really they should both be pushing towards one another, and if one breaks down the other should get through and be in a position to attack....this is the kind of situation where nobody loses , but nobody wins and nobody learns anything of any real value
Wing chun is very scientific in a sense, becuase the people who know what they are doing can explain everything about the style. It's not a question of finding explanations for kata etc, everything is known
.it's very deep
this is goodhttp://www.youtube.com/watch?v=xMzZL7MEqq0http://www.youtube.com/watch?v=kk_a52sxbcg