Squeeze

Maine Squeeze

I must confess, it never occurred to me how intensely gags are squeezed into a thirty minute comedy show. The rule of thumb is three gags per page (that's around ninety gags per thirty minute episode). Perhaps unsurprisingly, a large proportion of comedy techniques are geared towards squeezing every ounce of humour from those pages. So, going into the final (before submission) edit, I'm looking at every word in every line, making every word count.
Here're a few cool ways of mining that last diamond:

Topping the joke
A quick google comes up trumps.
Stan Laurel has an accident with a dump truck which leaves Ollie sat in his 'practically new' car, neck deep in sand (Blockheads). Super. Now they could move on to the next gag ... or, they could top the joke and add another punchline.
Stan begins digging out Ollie with his hands.
Given that all exposition - all set-ups - are expensive (and, as such, need to be blended seamlessly and amusingly into the forward momentum, such that they become indistinct from the other gags), it makes sense to get all the hits possible from them.

Repetition
Once we have seen Father Ted phone his friend Father Larry Duff with hilarious consequences, we learn that, each time Ted picks up the phone to call Larry, we're in for a wonderful gag. We're conditioned, and the gag is set-up by the merest touch of the phone and mention of Larry's name. Here are some of the consequences that befall Larry - the results of Ted's distracting calls:
(From Wikipedia)
These events include car and skiing accidents, an avalanche, a disastrous donkey derby, a very painful mishap with a stapler, an unlucky incident with a knife-thrower, being ravaged by a dozen Rottweiler dogs, and losing out on a £10,000 prize.
Moreover, it's basic good writing to reuse existing characters and props and the like.

Malapropisms
John Sullivan squeezed so much humour from potentially expositional/functional lines by having Del Boy remark 'Good to be back on the old terracotta'. And so on. I imagine that it's possible to imbue every single line of dialogue with an incongruity in this manner.