As far as the set-up goes I don't know
, srys... I don't use that set-up. Seems like it would be risky if miss-timed or read. It sounds interesting though, so I'll test it a bit tomorrow.
But I can answer the 6C6[C] question. Most of this info is unrelated to your set-up.
6C6[C] combos don't work on Len, White Len, Miyako, and the Nekos. Loli hit boxes are too small to hit. Unless you get a counter hit on something like a 5A6A~A stagger or a wall bounce, then 6C6[C] hits. Use 6C5A(wiff)6A(wiff)6A6C... mid screen and in corner.
On the flip side, 6C6[C] hits corner and mid screen on Riesbyfe, Arc, Wara, Nero and Ciel (and Archtype).
Every one else, 6C6[C] hits in the corner only. Use 6C5A(wiff)6A(wiff)6A6C... mid screen.
Also, I find the timing for mid screen 6C5A(wiff)6A(wiff)6A6C... on Kouma, Arc and Warc to be very... particular. Either it's not possible or their height must be controlled very precisely or 2C will hit invalid. Arc can be 6C6[C]ed but the others... Safer just to cut it short with one 6C rep. Or, 6C dash 6C also works, but it does a lot less damage for only 6% or so more meter.
-TexasTim-
-Edit #1-
I Tested the set-up on Miyako today. Works just fine on her. I'm not sure how to put the timing in perspective without doing the set-up on more than just Miyako and Ciel. However, it looks like you have to get right next to her and 6C before her wake-up animation starts. Make sure you're 6C dash 6C timing is as tight as you can make it so the 2nd 6C hits as soon as possible, and you have more time to dash in. I'll work more with that set-up on the rest of the cast.
Also a side note. It looks like this set-up is very vulnerable to wake-up dodge, shield and throw due to wiff 6C recovery. Especially wake-up throw.
-Edit #2-
Okay, I tested this a lot on every character. Here's my findings.
The key to setting this up is to 214C summon as soon as you can. You can delay it a bit with most of the cast, but with Miyako you cannot at all.
Vs Archtype, Satsuki and White Len you must delay your summon or it will totally wiff.
Vs Akiha you must 6C dash(lengthened as long as possable) 6C then 214C summon with no delay for you to be able to cross-up, however if you do not delay the summon will wiff. Therefore, this set-up will not work on Akiha.
Vs V-Akiha, S-Akiha, and the Nekos I am not able to cross-up at all, and don't think this set-up will work on them in that regard.
Please disregard my statment in Edit #1: "Make sure you're 6C dash 6C timing is as tight as you can make it so the 2nd 6C hits as soon as possible, and you have more time to dash in." This does not matter.
Hope this helps...