By this time in the run of Walt's TV show, very few new episodes were being produced.
This was one of the rare exceptions.
To commemorate the release of the recently published book The Illusion of Life written by legendary Nine Old Men members Frank Thomas and Ollie Johnston, this episode hosted by Disney favorite Hayley Mills was produced.
Although there had been books written about the Walt Disney Studios going back to the 1930's, their book came during a surge of books written about the Walt Disney Studios and became the standard textbook on animation principles.