The point is that the more of the details you have committed to memory, the better your able to "think outside of the box" because your limited cognitive capacity is not bogged down by the minutia. The analogy of fluency in natural language I think is very relevant. The difference in complexity of thought between someone fluent in a language vs someone just learning isn't a matter of intelligence, its a matter of having the building blocks of thought committed to memory. The more of the details that are second nature, the higher level of thought that results. I don't see why this is any different when it comes to programming.