I thought the 7 year cycle was originally designed with theatrical screenings in mind. During the advent of home video (which Disney fiercely protested as I recall) I think the idea of applying that principle to home video releases was applied. That was prior to Ebay, second hand video stores, and the ability of your neighbor to copy DVDs. Seems like the 7 year concept is kind of a moot point here in the early 21st century.