I'm working through a piano study (Burgmuller Op. 109, "La Separation" if it matters). I'm using this study to gain a better handle on large jumps in the LH and rapid chord changes. I think it's done quite well, but there are a few short passages, about 2 bars, where I often make mistakes when trying to play at speed. I can play through the passages if I'm going slower, and I know that it's just a matter of time before I get them down.
And therein lies the issue: I like the piece, but it's not one of my favorites. I really chose it for the technical skills it develops. I feel as though the piece has served its purpose, and that I would probably get more out of moving on to another piece that has a similar focus. However, I'm not sure if I can distinguish between: "These bars are just difficult" compared to "I lack the technical skills to play them properly". If it's a technical problem, then I should stick with this piece until I master the technical skill, yes? On the other hand, if it's just a difficult passage, then presumably getting it perfect won't really move me any closer to my goals.
If my goal is to be able to learn any piece faster, should I move on to another study to more fully challenge myself, or should I stick with this one until it's perfect? Or, in other words: if I stick with this piece, will I essentially just be getting better at playing it, without much benefit to my general skill set?