Okay, so now is my big question.
So people generally agree human reaction averages around 12 frames. So say you're in a tourney. You grabbed MK. He's at 100% percent, near the ledge, but not so much that you can't do a grab release set-up.
How fast he gets out is variable, meaning up to the MK user himself. He can get out really fast, or really slow, you don't know exactly. Fair, dash attack (lol it's easier to buffer a dash for the tipper one than this Nair thing) or Dolphin Slash, which if he doesn't DI, he will die, are all things you can still do within human reaction while MK is helpless. Buffering a dash from grab is difficult since doing it too early would mean a Fthrow. Which creates this problem.
From the initial release frames, which is like 6 or 7 frames, you must immediately buffer and hold a dash, then rising Nair. That's almost a half of what average human reaction can do.
Furthermore, I've never been able to consistently tipper the last hit. I've found that the first hit naturally tippers, but even if you DI back as you nair, the second one usually does not. If you do succeed doing this in the heat of battle, I would be amazed, furthermore if it was tippered.
So...is this even any good in application, or simply the theorycrafting we Marths love?
It does look sexy though, I'll give Shaya, Ulevo, and co. that much. ._.