That's weird, both Interdimensional Cable episodes are in my top 3-5ish for overall episode enjoyment. I'm able to sense the ad-lib, unscripted nature of most of it, and it just cracks me up that they turned a bunch of random ad-lib, unscripted shit into a solid cartoon episode. Meeseeks is up there, as is the Alien Matrix one right before it (S1E4 I think?).
The actual Get Schwifty song was pretty great, but I'd agree the overall episode was one of the weaker. Weak for R&M is overpoweringly strong for most other shows though, IMO.
Take off your pants and your panties...