My DS4 does this as well, but I bite my tongue a lot and try to keep the critism to a minimum because DS4 and I are both perfectionists. I find myself doing this with drawing and writing as well--letting his mistakes go without comment for fear of stoking perfectionism. Maybe I'm going too far in the other direction though. I don't know. To some extent, I'm also still so amazed that he's reading as quickly as he is at age 4 that I don't see any urgent need for improvement. I like ColinsMum's idea of focusing not on DS4 and the way he's reading, but on the needs of the listener. That might get to the issue while avoiding direct criticism altogether.