-Dem0-

Ehhh, it didn't take too long. It's mainly a case of playing until your mind and hands readjust to a new button layout (so for me the hardest part was the A, B, X and Y buttons). Just keep at it and you'll get used to them in time. It might be a bit harder for you, since judging by what I saw last night, you seem to have attempted to learn a select few characters and the "competitive" techniques they're capable of. I've never tried to learn the characters, heh. But I'm sure you'll be able to learn again with enough practice.

But all that said, if you intend to learn the Wii U Pro Controller, keep in mind that you'll probably have to learn to adjust yet again due to the different button placement. But that's just how gaming on Nintendo consoles is, what with the company changing the controllers all the time. =P