There's a certain freedom that comes with creating an animated comedy for adults. Characters and stories rooted in reality can suddenly veer off into the absurd or impossible without completely derailing the plot, because the viewer has grown up expecting cartoons to be zany. We expect and accept the unreal in animated television — on some level, we're always aware that whatever's happening is taking place in a different world, with different rules. It's this juxtaposition that lets the best episodes of the Simpsons touch our hearts while simultaneously attaining a nearly hallucinatory level of absurdity, and allows a show like Family Guy to beat on the corpses of the same old audience recognition jokes and pop cultural references week after tired week.
A good animated comedy will take advantage of the duality, deftly placing interesting characters in situations that strobe between reality and that other world.
And Archer is an excellent animated comedy.