Family Guy (1999)

The cutaway gag made into a whole engine. Seth MacFarlane's show will leave the plot for a non sequitur flashback at any moment, which means a joke lands every few seconds even when the story stalls. That makes it the purest example here of quantity as a strategy: when one gag misses, the next arrives almost at once. It also means the hit rate varies more than anything else on the list, and the humor is deliberately crude and offensive. If your idea of joke density is sheer volume, nothing else fires off asides quite this often.