I have no experience in writing novels, but I do have quite a bit in being a student. I always cringe a bit at these purists thoughts of "you retain better when you write by hand" and "your creativity is better". The process of studying and learning is much, much more than just writing things down. Even if it was true that it's better to write by hand, the amount of productivity you lose by not having things in a digital format (weight, indexes, search, linking with other sources, corrections, drawings, etc) is just not worth it.

Not to mention that I think it's misguided to solve a problem by attacking it sideways. Writing by hand to fix excessive correction doesn't actually fix the issue, it just sweeps it under the rug. Maybe it's just delaying it until the point where the novel has to be reviewed and now they want to do the same corrections, but harder.