Knuth says in the Preface to Volume 1 that "A shorter version of Volumes 1 through 5 [chapters 1-10] is planned, intended specifically to serve as a more general reference and/or text for undergraduate computer courses; its contents will be a subset of the material in these books, with the more specialized information omitted."

I realize he can't shorten what he hasn't written, but I wish he had been able to write this shorter version years ago, and then work on filling in the details in the now-ever-expanding sequence of in-depth volumes.