Emulator

No, that's just the game. You can use the C-stick for smashes every once in a while, so you don't wind up with spammers like in Melee.
If it's any consolation, you shouldn't be using it anyway if you want to beat someone.

thanks billiard26, i set it to 25 and it fixed it perfectly.

i never thought of the c-stick as being cheap, i've just always used it... and i doubt the game was designed to be like that because it works on the wii and on dolphin it is very inconsistent, sometimes it'll work perfectly for a good minute. I'll think about trying to get used to playing without it though, as none of my friends use the c-stick.

@jackrobe:

You don't know how to play. The C-stick is the only way to pull off snakesliding and other combination moves. This is breaking the ability to play this game at any serious competitive level.

@jackrobe : hum you never played ssb or what ?? try to upair just atfer falling from a platform without jumping !!! C-stick is sreally important in a High Level match, stop talking and play the game man

It's been a while but I found a fix for this problem.
Setting the Square Stick parameter to something high (I just use 100) fixes all issues mentioned in this thread in my case.

..and I had to set a small Deadzone (~30)

I'm not having issues with the C-stick, but I'm noticing a similar consistency issue with Z.