[@Shoryu Magami] I learned about the terms through /tg/ people, where fluff and crunch are two halves of a whole.  So that's where most of my ideas for that come from.  Also there's fluff like...feelsy-things, and that's good too, but a different concept.  <3

[@Gowi] Padding and filler have negative connotations (at least to me) because the implication is that they are unneeded -- it's stuff you're adding, be it for wordcount or just to look impressive.  Fluff and crunch merely describe the type of details you're working with.

[@MissCapnCrunch] Your SN and signature are timely and highly amusing.  <3