I just stumbled upon this earlier, and had no idea the Dregs appeared on a Late Night Talk Show, especially as recently as 1993.
But my reaction was while their performance is good, why on EARTH did they have to play a bloody MEDLEY? And for that matter, throwing in COVER TUNES within that.
I wonder if when they were asked on to the show, they told the producers the song they wanted to play was 6 or 7 minutes, and the producers said to them they couldn't do it, due to length, so they had to do something shorter.
It kind of brings up the idea of why for the most part, prog, at least when progressive rock (or jazz-fusion in this case?) when doing what they do best, doesn't seem likely to fit the confines of commercial radio or in this case, Major Network Talk Shows time restrictions.
I remember back around 2002/2003 when Dream Theater's Six Degrees of Inner Turbulence was out, they were asked to go on The Today Show I think it was, and the producers only wanted them to play stripped down, shortened acoustic songs. And the band declined.
Which kind of makes me wonder if other prog groups in the past either turned down offers due to what the show asked of them, or when they did appear, had to pick a song to play that fit the requirements of the show/producers.