More wisdom from Mr Wendig on the elements of story:
The throughline is an invisible thread that binds your story together. It comprises those elements that are critical to the very heart of your tale — these elements needn’t be the same for every story you tell but should remain the same throughout a given story. You don’t switch horses in midstream, after all. Because that’s just silly. You have a horse. You’re in the middle of a stream. That horse over there, you can’t trust him. He might be a total dick. Plus, if you leave your current horse, you’ll hurt his horsey feelings. Do you want that on your conscience? Can you handle seeing your ex-horse try to drown himself in the very stream you just crossed on another mount? You bastard.
Not Enough Words 
Hurt his horsey feelings… BWAHAHAHAHAHA!
OMG! Did someone just use “comprise” correctly? You did, you did! This makes my fuzzy little heart *so* happy!
“Comprise may qualify as the most consistently misused and abused single word in English.” —Wolf’s Style Guide
Lolz, I see your point, poor horsey!
This is a very humourous way to remind your fellow writers to stay on track.