On the 200% meter knockdown setup from those videos:
Went to training to mess with it a bit, the damage loss isn't that huge, something like 400-500 less compared to your standard corner bnb when started from 5B. Linking 236A6C right after works on the Lens also, so that was his mistake.
That said, I kiiind of liked it at first but at further thought, it really looks like it's useless. 200% meter is just way too much for it, like you pointed out. Sure, he only used it when at MAX, but when you're in MAX isn't it just plain better to use your Arc Drive for the same result? Damage might be higher, and it's much more safe in the sense that dropping it is almost impossible. The only problem is you're missing 100% meter for using the AD on MAX.
Also, you can't start your combo off 2A because it's required on the actual combo.
And just to add something else to the post:
http://www.youtube.com/watch?v=IJIm1jNLAscFound it while browsing the
MBAA BBS out of sheer boredom, 22B links into 22C. Exclusive to CC? I don't have the PS2 version to test anymore but it doesn't seems new, still recorded because I found it funny, even though it's pretty much useless. Someone also mentioned 22C connecting on Nero after H 5A6AA but that doesn't seems new either and might be useless.