Originally developed as 'short' for "rubber-hosed", as in beating someone or something severely with a rubber hose. It quickly expanded in popularity and use to mean pretty much anything or anybody really messed up.
My college fraternity in Mpls, MN (Univ of MN)starting using this as 'code' around parents on parents-day at the fraternity; since we couldn't say something was "f*cked-up" in front of our parents. This was back in early 1970, a couple of years before Dave Thomas and Rick Moranis started using it in SCTV Doug & Bob McKenzie episodes. Since my fraternity brothers traveling to northern MN, Chicago, and even Canada on school breaks; I beleive SCTV picked it up from my fraternity brothers using it and spreading it around. I do. It was at least a couple of years before them that my frat-house brothers were using it.
As in "that's really hosed" dear brother, or
you're gonna get "hosed" on that test you didn't study for!
For Homecoming in Fall 71, myself and a fraternity brother were responsible for outside frat-house decorations. We of course got drunk, and at the last second hung a bedsheet from the front of the frat house 2nd floor porch railing, with "Hose the Hawkeyes" painted on the bedsheet!
Just before passing out I draped about 8 feet of gardenhose over the front of message. we were a real class-act backed then.