Hi Dave,
I don't think grappling and Chin-Na where often expressly taught by Yip Man. Others like Yuan Kay San people claim to have more in their system. I think others in Yip Man lines have added much to their system, especially after the popularization of MMA.
To go back to my comment that is surely to cause some discomfort, I don't mean to imply Yip Man wing chun has no Chin-Na. Quite the contrary. I think it is in the system, I just don't think that it self was taught specifically. I suspect it more rose opportunistically and probably wasn't valued as much as hitting by some. My view is that the chain punching you mentioned is very valuable in a certain context. But it is a lowlevel skill that in of itself can be learned very quickly. As is evident by the many discussions of the 1950's roof top challenges. But wing chun is much much more. And any decent teacher that really knows wing chun should be able to show you how to do more than "beat the hell out of someone".
I don't like throwing because it presents a problem, or atleast it can. If I take the trouble to get into contact range, I really don't want to get out of it. I think there is a dangerous area just outside where a good striker can easily outclass me. So if I get into my range I want to stay there. If I throw (depending on the type of throw of course) my opponent may be outside my range again. I am back at square one if he isn't hurt by the throw and gets up quickly. I perfer to control him. break down his structure and prevent him from countering. I hopefully can affect his balance, structure, and stability. I am not too interested in locking or trapping, but often the result is similar in that the person is unable to do much. Atleast that is the goal I am going for.
I think Chin Na itself is not lineage specific, so there is nothing specifically preventing you from using it in wing chun. Though I do think chin na specifically has a different goal and is applied somewhat differently, meaning some techniques may be at odds with some wing chun principles. But there I think you can use them as they present themselves and perhaps with some slight modifications.
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