*I'm not sure if this has already been discussed before or not, but I didn't find anything on the forums/wiki so I'll just post it here*
Until a few hours ago i thought that charged attacks were completely uneffected by ASI, but I seem to have found an exception. Today I made a Wild Hunting Blade, just for fun, but i noticed that WHB's charge attack is executed significantly faster if you have high ASI. I don't have the right instruments to properly measure this speed boost, but the difference between no ASI and ASI max is quite noticeable even to the naked eye, if you want to try it. This doesn't only apply to the WHB, but even to the DVS and all the cutters in general (even the to Red Saber).
I also tried this thing with other weapons, mostly focusing on those weapons whose charge attack is composed of "multiple attacks" (like the final flourish, the antiguas, etc.), but it only seems to work with the cutters.
Oh well, I hope this can be useful in some way...
/shrug
Should work on everything, just the slower the charge attack the more you'll notice it.
Blitz benefits from having it, with more ASI you can finish your charge and get out of the way quickly (or start another charge sooner).