I actually saw the "special longer version" in its first broadcast, on commercial U.S. TV in early 1983, with someone who'd never seen it in the theater (whereas I had, twice, in late '79). With all the commercial interruptions, it was difficult for my friend to say anything but "Huh?" in reaction to what she was seeing.
I don't think I ever saw TMP again, except for the odd segment on TV, until obtaining the DE on DVD (cheaply, but new) about 5 years ago. However, my 8-track tape cartridge of the soundtrack LP received much play throughout the 1980s and early '90s. (Also I've long owned the paperback fotonovel; nice color reproduction.)
I presume the impetus for creating the SLV came from the network that broadcast it. This sort of thing had been done in the '70s with such theatrical movies as Earthquake (which added more than 25 minutes), and of course it happened on a much smaller scale with TWoK on ABC a few years later. But does anyone here know a source for the details of putting together the SLV, such as who took the actual editing decisions?
I just inherited my first LED TV with HDMI connectors and will buy my first Blu-Ray player soon to go with it - and I'm not going to be disappointed no matter what the DE DVD looks like when played that way.
EDIT: It's high time, isn't it, for my next promotion? Jeez. I know Commander's nothing to sneeze at, but what does a guy have to do to reach Fleet Captain around here?