If you've spent any significant time trying to learn classical music on an instrument, then you may have encountered a common problem: You keep making the same mistake even though you know what the correct notes are. It might not happen every time, and when you shine a light on the spot and practice it slowly you can get it, but put some pressure on and it becomes a liability. Worse, it's the same mistake each time: for example, why does my left hand keep playing a B octave when I know it's A flat?!!! The usual methods of troubleshooting aren't working. What do you do?
I have good news. That pesky persistent wrong note or rhythm is your inner creative voice rearing its head! You see, it has its own ideas about where the music ought to be going, composer be damned. Maybe it really wants a Neapolitan harmony instead of just a minor ii chord. Maybe all that New Age you listened to in your free time is causing you to insert a different mode into Schubert. Whatever it is, it will not be denied, so you'd better start paying attention to it!
In the past, some traditions of pedagogy would have you beat your ego into submission, squashing it, pulverizing it until there was nothing left but the composer's intentions. "Who are you to question Beethoven? The score is the final word!" You'd hammer away, over and over and over until the right notes were so ingrained into your muscle memory that you didn't have any other options but to play the right notes. But you know what? That takes forever. There is a faster, kinder, and more reliable way.
The answer is to do what you want! When you find an intractible spot, turn your attention inward. What is your inner musician actually trying to express here? Try it out, no matter how outlandish it may seem. Try that blues riff out in your Bach. Throw that samba rhythm into Mendelssohn. The point isn't to make it sound good. It probably won't! The point is to acknowledge your natural musical pathways.
When I was learning how to improvise, I spent a lot of time cringing. Thank goodness I was still single back then. I'm a sentimental guy, and what came out when I let my fingers go was a lot of cliche sappy stuff. It was rough. Once in a while I would come up with something that wasn't too vomit-inducing, and I'd polish it up into something that was presentable as long as I didn't dare to call myself a composer. But eventually I noticed that I seemed to be running out of ideas, because I was making the same moves in every improvisation. There seemed to be these kinds of deep grooves in my toolkit of chord progressions, melodic gestures, and rhythmic motifs that limited me to writing essentially the same few pieces over and over. Partly it was by choice: I gravitated to these sounds because I liked them. And partly it was out of habit, because either my ears, my fingers, or both had gotten used to taking the same turns at every intersection. The compositional solution was to deliberately avoid these habitual answers, and scour the work of other composers for new ideas.
But in the prior example, we are not composing ourselves, but trying to come to terms with someone else's composition and musical language, which may be decades or centuries removed from our own. And our inner composer is getting in the way. Now, to defuse this conflict, we need a mediation. Both sides need to have their say. So, give your creative voice a fair hearing. Try out its ideas for real, as if you were going to perform it that way. Go all the way with it. Make whatever changes you find necessary to the score in order to make your own ideas work. Then, go back and play what the composer wrote. You may need to go back and forth between the two a few times or more in order to feel that each is getting its best representation.
After giving both sides an equal opportunity, chances are one option will seem superior to the other. Having acknowledged your personal musical instincts, you can make a conscious choice to play the passage in question the way that seems best to you. You now have ownership over what was formerly a musical thorn in your side, and the problem should disappear.
And if you decided to go with your own musical instinct over the composer's, more power to you. Chopin shouldn't have written an E flat there anyway!