Drudging my way through these later seasons, I've come across several episodes which have not been good. Whether its because the premise is just awful, the jokes are either non-existent or just bad, or a combination thereof, these episodes are the bottom of the barrel for the series, indicators for any new writers for the series to take to heart as to what not to duplicate.
As I continue to make my way through these newer episodes, I will likely update this page when needed.
T-#10: Mathlete's Feat
Season 26 | Episode 22-574 | Score: 4.0
Pointless references, dull plot, a lot of filler because the dull plot was too short, oh, and lots of bad jokes. That's how you (barely) make the bottom ten.
T-#10: That '90s Show
Season 19 | Episode 11-411 | Score: 4.0
The first episode to air after the similarly awful E Pluribus Wiggum, the problem with the episode isn't the fact that the show get retconned by the 90s, its that it does so goddamned poorly it hurts.
#9: Love is Many-Splintered Thing
Season 24 | Episode 12-520 | Score: 3.9
Marriage theme. Bringing back Bart's girlfriend eleven episodes later just for them to break up. Lisa. Large amounts of Woody Allen. Yeah, it deserves to be here.
#8: Moe Goes from Rags to Riches
Season 23 | Episode 12-498 | Score: 3.7
Moe's rag, which is Moe's best friend, talks about its origins as a demonic tapestry and all the other crap it went through, none of which resembles comedy.
#7: Midnight Rx
Season 16 | Episode 06-341 | Score: 3.6
An episode where everyone is popping prescription pills thanks to Homer and Grampa's efforts to smuggle in cheap drugs from Canada isn't even as funny as it sounds, and it sounds as unfunny as possible.
#6: The Serfsons
Season 29 | Episode 01-619 | Score: 3.5
While its the same score as #5, I'm giving this the tiniest slack as part of its problem was ("simply") its terrible execution of a braindead idea, though make no mistake it is full of terribly written jokes as well.
#5: The Greatest Story Ever D'ohed
Season 21 | Episode 16-457 | Score: 3.5
Maybe it was the religious theme. Maybe it was the really annoying tour guide, Or, maybe it was that this episode was completely unfunny as a whole.
#4: Bart-Mangled Banner
Season 15 | Episode 21-334 | Score: 3.4
A temporarily deaf Bart unknowingly moons the American flag, setting off a wave of political agenda jokes that never makes for actual comedy.
#3: Blame It on Lisa
Season 13 | Episode 15-284 | Score: 3.2
The Simpsons go to Brazil to find Lisa's sponsored child who had gone missing, then Homer gets kidnapped. The problem with this episode? All of the jokes were crap.
#2: Alone Again, Natura-Diddily
Season 11 | Episode 14-240 | Score: 3.0
A voice actress has a contract dispute, and leaves the show. Producers natural response? Kill off one of the characters she voiced in Maude Flanders, under the justification that future Ned Flanders episodes would have potential, because A Star is Born Again and I'm Goin' to Praiseland were really worth it!
#1: Married to the Blob
Season 25 | Episode 10-540 | Score: 2.8
How does an episode fare worse than Alone Again, Natura-Diddly? By being an episode composed solely of comic book and anime references which, mind you, is not actual comedy. The 'jokes' aren't any better, either. Not even Stan Lee was able to prevent this epsiode from being the new worst Simpsons episode of all time.