So far I don't see ANY indication I can watch 4 programs in this mode. Unless by program you me 1 cable channel, 1 app, 1 browser, etc. Your cable box usually limits what channels you can display in that input at a time. Very few decode more than 1 at a time.
https://www.google.com/search?q=HDM-SWITCHPRO-VW4&ie=utf-8&oe=utf-8 finds what some are looking for but to date I've yet to find a TV do true quad.