Negima! canon is that anyone can learn to use magic. Most people are just very, very bad at it no matter how much they practice and study.

Like anyone can learn karate, but only a very few people are anywhere in the neighbourhood of Bruce Lee when it comes to martial arts.

But! Cheating her way around that comes after most of the festival arc. And possibly after a tragic scene where she goes back to her timeline to unravel with it before a slightly earlier version comes to/back to the bar.