DS was similar at that age: memorized books; spelled phonetic words such as tomato, polenta, etc; knew a lot of sight words including lengthy relatively uncommon words e.g. flamingo. I picked up a second hand phonics book thinking he'd be able to use it 6+ months down the line. His eyes lit up when he saw it, we read it together once, and he was suddenly reading. I think he just needed the key to help him with decoding.
He did insist for a long time that only phonetic pronunciation was correct - we had lots of arguments about how rule-breaking words *should* be said vs. how they were actually pronounced. His reading vocabulary was far larger than the spoken vocabulary that was typically used in his environment. But at 5 he gracefully accepts correction.
