Hmmm, this might be kind of similar to what the Demeter system actually did. With Demeter, you would provide some sort of machine readable descriptions for your data structures. Once you implemented this description, you could ask Demeter to fetch you all sections of a book, or all sentences of it, or what have you. If you were to then change the representation of the book, you would't have to change any of the client code--you'd only have to change the machine-readable description of the data structure. Then when client code asked Demeter to fetch all the sentences, everything would still work fine.

Maybe the best solution is to just resuscitate Demeter! Though apparently nobody actually used it either.