My only gripe with T&T is what is arguably the biggest laugh-getter in the whole episode... Worf's "We do not discuss it with outsiders" bit.
I just think that opened up a whole unnecessary can of worms. Hindsight being 20/20 I think it would have been far funnier to have Michael Dorn suddenly look like a 60's Klingon...and have no one comment. Would it have confused some casual viewers? I'm sure. But realistically, by that point in DS9 how many casual viewers even were there?
I loved that bit.
So do I. It's joking with Trek continuity, which struck me as fine. Trust me, the Klingon forehead debate is something that existed prior to this episode, so it's even nudging in the general direction of Trekdom.
And "Trials and Tribble-ations" is probably DS9's most successful episode among casual fans, for obvious reasons. It's about the one episode of the show most casual Trekkies are likely to have seen.
It's also great, and I may actually like it more than the original episode.