This is a good question. Thanks for asking it. It’s one I get asked often, so here is my answer for you and for anyone else who has come across this in the past and finds it a mystery.
When children can read well, they have reached the point where they have each word form entrenched in their long-term, visual memory.
For example – They know that the word ‘apple’ has the same visual format 1 a, 2 p’s, an l and an e. It never changes. That formation of letters is always going to be ‘apple’. For this particular word, the decoding process is not needed anymore.
When reading they go straight to the prefrontal cortex, which has this visual format of the word ‘apple’, stored. They retrieve it, add meaning to it and move on competently with their reading.
This is how all good readers read, jumping from one word to the next, as they recognize its form, visually. In fact, really good readers might only look at the first two or three letters of a word and predict what the word is from the semantics, the meaning of the previous text in whatever they are reading.
Super-fast readers do this all the time.
If they make a mistake with their prediction and they realize what they are reading doesn’t make sense. They’ll then go back and reread the sentence or the word to clarify what the word they mispredicted, actually was.
I am predicting that this Grade 5 child has an excellent long-term, visual memory. This is often why people with reading difficulties go undiagnosed, because they come across as competent readers, and they are to some degree.
Phonetic decoding is a whole different skill set and this is the part that stumps them. Words they have never seen before and don’t have a visual format for, stored in their long-term memory, stop them in their tracks.
These children need decoding strategies, such as those I teach in The Ten Minute Tutor®. Breaking words into syllables as you mention, teaching the phonetic code or… the symbols, sounds and spelling rules associated with words will help this boy immensely as he moves through the school years.
There will always be new words, as he learns new information in his subject areas.
Your job and mine, is to teach him how to decode those words he has never seen before and to remember the visual format of them, so he can get them into his long term visual memory in his prefrontal cortex.
I hope that helps.