Visit and contribute to the 4 Blocks and Building Blocks chatboards, and subscribe to a Four Blocks Mailring. Bookmark the 4 Blocks Center . He doesn't use the letter patterns he knows. He stutters and struggles with the very same words he can spell and write fluently when looking at the words individually. This word-calling practice is a rather common occurrence that is not isolated to the lower grades.
Many children develop the ability to decode words as a fairly singular operation.
However they've learned to do it, they do it skillfully. If you believe that reading is gathering meaning from printed words, then NO they aren't really reading. They're doing one part of the complex process of reading which is decoding, but they haven't achieved the most critical part of reading-comprehension. There could be any number of reasons. One could be something we've done.