Rewriting is an interesting exercise. I don't mean rewriting your own stories - rewriting someone else's. That's what I did for my latest story, Severus Spike. There were enough parallels between Snape/Lily/James and Spike/Rarity/Blueblood that I decided to retell a critical scene from Harry Potter with canon ponies.

I had read all the Harry Potter books, but I never appreciated Rowlings' style until I tried to change it. Having to change parts of each sentence forced me to examine the other parts as well. Sentence after sentence, I copied the original, changed what I needed to, then sneered a little inwardly, rewrote the rest of it reflexively in my style, and looked at the result and said, "Wait, her way's better."

Changing some of the characters meant I had to change some of their actions and reactions, and figuring out how these changes should propagate through the story gave me a better understanding of why she did what she did than just reading or copying her text would. Ultimately, the story doesn't work as well with Spike as with Snape; but I might not have realized why simply by reading it.