For what it's worth, if I'm writing a quick script I'll often write a few quick comments first (e.g. "Load data from file", "Connect to API", etc) before I start writing any code, just to plan it out. Similar to how many people will create a bunch of empty methods when creating a new class, before fleshing them out.
Rapid-fire editing with text objects [...] ought to work pretty well on screen.
I wish they'd just do away with the rapid-fire crap altogether. It breaks the immersion. A mildly witty easter egg does not compensate for making every nerd in the audience of your nerd-movie cringe...
Just show some realistic typing, with mistakes and perhaps a quick copy/paste.
I'm not saying anything extreme, just something realistic for an accomplished vimmer, which is impressive enough and would do the opposite of making nerds cringe.