Each couplet describes an iconic duo or trio whose elements are always listed in the same order.

# Couplet Meter Iconic Set
1. It’s a tasty quick lunch with no need for a fork,
though not kosher, alas - one ingredient’s pork.		 duh-duh-DUH Bacon, Lettuce and Tomato
2. What a song! What a hit! What’s it mean? What is “it”?
Huey knows, I suppose. Let us ask what he’s writ.		 duh-duh-DUH Pop, Lock & Drop it
3. These central moral opposites
aren’t truly how the real world splits.		 duh-DUH Good and Evil
4. They’re pinched or shaken. Also they’re
a hip-hop group and shade of hair.		 duh-DUH Salt and Pepper
5. Do and fail and then you’ll fail less -
that’s the essence of this process.		 DUH-duh Trial and Error
6. They comprise all your life, and if you give rebukes
out to others in need, they are holiday spooks.		 duh-duh-DUH Past, Present and Future
       
1. This dad and his boy and their nebulous sidekick
are etched in bright glass ever since the boy died quick.		 duh-DUH-duh Father, Son, and Holy Spirit
2. If you’re aglow it’s the one way to go, you know;
winds won’t just blow if you wait on your toes - get low!		 DUH-duh-duh Stop, Drop and Roll
3. What these elements soulfully ask you to find
is a day in September lost deep in your mind		 duh-duh-DUH Earth, Wind and Fire
4. From what all I can see, they comprise every tint,
though they don’t if you paint, and they won’t if you print.		 duh-duh-DUH Red, Green and Blue
5. When you’re playing this contest of cyclic defeat
if you’re two steps ahead then you’ll surely be beat.		 duh-duh-DUH Rock, Paper, Scissors
6. These thinkers never met, but still
they’ve oft conversed descending hills.		 duh-DUH Calvin and Hobbes

It turns out the number of elements in the set (two or three) always matches the number of beats in each foot of the couplet. As hinted by the flavortext, one then takes the element from each set corresponding to the stress in the foot. For example, the first couplet’s meter is duh-duh-DUH, so one takes “Tomato,” the third element of the set. This step was tricky, but it can be guessed from the fact that, though every couplet’s in tetrameter, the location of the stress is varying, suggesting it’s used for something. Taking the letter of the stressed set element corresponding to the index of the poem (i.e. 1 through 6; correct letters bolded above) gave TRIPLE on the first page and STRESS on the second. A metrical foot composed of three stresses is a MOLOSSUS, the final answer to this puzzle.