Are we really supposed to believe that Cole and Brent are such an odd pairing that Neil Simon-esque antics are about to ensue? Is Brent known to be particularly neat? Is Cole known to be particularly slovenly? Not that I'm aware of, and I've been reading PVP for quite some time. As a reader, I don't buy Jade's theory for a second, ruining the strip from the start. These guys are best friends after all.
(Aside: the fact that Brent is a Mac guy and Cole presumably isn't is not sufficient motivation for Jade's statement. If we were talking Brent and Francis, maybe.)
(Second Aside: Commenters just reminded me of the storyline where Jade moved in with Brent and he acted like a total girl. [Looking for links.] I stand corrected on this point. It doesn't change the fact that the first panel totally set up a predictable joke.)
Aside from that, the joke itself is presented in a fairly weak manner. Yes, this is hyper-specific, but these are the things that get under my skin.
The joke is supposedly in panel three (panels two and three shown below), with panel four simply extending it:
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First: There are only four panels to work with. Why throw away the last one with a second, weaker, punchline? Jokes require a setup and a release -- use the extra panel to extend the setup, making the reader anticipate the (unfortunately predictable) release longer.
Second: The order of events in panel three completely ruin the joke. The way the panel is laid out we (first) read Brent's line ("There, now the table's finally level...") then (second) "hear" a "KLUNK!"
Wouldn't the joke be funnier if the "KLUNK!" came first?
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Yes it would. By introducing the sound effect first, you allow the reader time to wonder if, because Cole is Oscar and Brent is Felix after all, Brent has just hit Cole over the head with the ashtray he brought "in here for a reason."
But wait! He didn't! He's an Oscar too! Those rascals will get along just fine and they can finally.. build their.. beer can pyramid.
(Seriously -- that was the best option?)