I think what DS claimed above is supported by the scene where Naruto was doing the leaf cutting training and one of his clones made a breakthrough and and then dispelled itself and instantly all of the clones learned the information that had been gained by the dispelled one and started using it in their own training.
In fact, I think its reasonable to assume that the chakra that is distributed back to the collective is the actual vehicle for the knowledge transfer in the first place. When you add together the fact that Kage Bunshin dispelling returns knowledge to the collective to the established fact that a piece of a person's chakra can contain all of that persons knowledge at the time the chakra was separated from them then it stands to reason that the reason the Kage Bunshin knowledge transfer works the way it does is because the chakra of the dispelled clone is returned to the collective and their knowledge is integrated.