My DD was clearly desperate to know how to read at 5, but just as clearly could not read. We even worked on the Teach Your Child to Read in 100 Easy Lessons book, at her request, and hit a wall relatively early on because she couldn't blend sounds. While I don't disagree that it was a mental block, it was not a mental block that was within DD's conscious ability to remove.
But yeah. One day she couldn't read at all, and the next she could read kindergarten books, and a week later she could read 3rd grade books. One day she couldn't walk, and the next, she walked without falling down (and without ever having crawled or cruised). One day she didn't talk, and the next, she didn't stop talking. One day it took her 45 minutes to do 3 homework problems, and the next she cranked out 3 full worksheets at the end of the school day fast enough to avoid having homework. I rarely see incremental improvement over an extended period of time; she struggles and makes no visible progress until suddenly she wakes up competent. She is the girl who goes in fits and starts, and she's been that way about almost everything, for her entire life, so I think that's just the way she is.
