No, that's not how it works. Online and offline operates differently from what I observed trying the game out on a toaster.
If you drop frames in training mode (offline modes I assume) below a certain threshold the game speed slows down accordingly like in SF4. Dropping to 55 still doesn't slow down the game in this case, for example.
When you're connected to an opponent, though, every time you drop frames the game speed stays the same and you sort of just skip frames. So the CA animation runs on time but just looks choppy to you (skips frames). So it doesn't make a difference for your opponent at all.
I'm not sure if the game speed is tied to the person with higher performance or if it's set. Like if both people were playing with shitty PC's would it slow down the match in that case or if they both run at the speed at they're supposed to? Regardless, it never matters as long as you're not the one playing on a toaster.