> He explains that for him, draft #4 is the draft after the painstaking labor of creation is done, when all that’s left is to punch up the language, to replace shopworn words and phrases with stuff that sings.
None of that suggests the writer is looking to use obscure words. I know the writers you're talking about as well; they're just doing it badly, or mimicking what they think a good writer does.
Compare:
Todd opened the curtains and the room got brighter
with:
Todd parted the curtains and sunlight streamed into the room
Both describe the same thing, and both use ordinary words. But the second one paints a better image in your mind. Of the curtains revealing the window behind them, of the way the room gained illumination, etc. It's livelier.
Or, let's say your marketing team proposes a new slogan: "Our intention is to make sure you're satisfied". A good writer takes a crack at it and comes up with "We aim to please".
First one sounds corporate and boring, the second one is friendly and informal. But both use words that everyday people would understand.
If you've just finished a draft of a few thousand words, a lot of dull phrasing will have made it into the writing. While writing those drafts you were focused on the narrative or plot or whatever. Draft #4 is when you comb through it and look for crusty phrases, replacing them with "stuff that sings". It needn't be garrulous ;)