In the early years of Nick at Nite, Nickelodeon's night-time "alter-ego", if ya will, ran a series of interstitals culled from a series of short educational films produced in the late 40's and early 50's. These films were re-edited under the umbrella title, How to be Swell, which, in a way, mocked those same films in a tongue-in-cheek manner.
Take this sample for example. The footage is taken from a 1947 "Shy Guy" short that starred a young, future 60's icon, Dick York, later of Bewitched.
You think maybe the folks that put How to be Swell together ultimately had a hand in the development of [adult swim]? Similar snarky attitude.