The emphasis is not on retrieving intact knowledge structures,
I liked this quote because, in the context of school/academics, our learnings usually needed to be recalled in an "intact structure" as proven this is not the easiest task to do. However, the lack or failure of this task does not mean that the "learning" and knowledge are not in the individual memory or that they lack understanding. In the real-world context, the application of knowledge comes in many forms, therefore calling for different forms of recall (ie. providing learners with the means to). This was described perfectly in the word "assembling" of prior knowledge from diverse sources to be applied.