While this was a pretty decent episode, it's one that makes me understand why ratings were beginning to drop by the fourth season. There's a formula to this show and after awhile it starts to get a little stale.
Also, if I recall correctly, in the fourth season QL was on against something else that turned out to be more popular, although I'm hard-pressed to remember what it was. I had a co-worker who watched QL and she stopped right around Season 4 because she and her husband started watching whatever it was up against because they decided they liked it better. So I think even long-term fans were beginning to tire of the show a little by this time.
I'm pretty sure it was up against 'Full House'. That's where the 'Stand Up' episode came in - they got Bob Saget as a guest star to try to pull that audience back in.