I don't know that I agree with your point about the Starship Exeter
script. From what I recall there were other, external reasons that had nothing to do with the script that led to the choice they made to mine footage from Act 4 to complete Act 3.
Regardless, if there's one thing I've learned from my seven years working in Hollywood, it's that half of filmmaking is just problem solving. Working in writer's offices, I learned a ton about writing for TV. At one point, I spent a season working in post production on a show, and was very surprised at how much I learned about writing from that experience, sitting in on edits and mix sessions with our showrunner. You pick up things in those sessions that might never occur to you in your writer's room. Too, you learn how to "write in post" -- what problems you can avoid, and how to fix episodes that might otherwise not work as well on screen as they do on the page.
A great example: Ron Moore's Battlestar Galactica
did an episode called "A Day In The Life" following a typical day for Adama. It happened to also be his wedding anniversary with is (now dead) ex-wife. So on top of the daily routine, the trials and tribulations of being the commander of the ragtag fleet, we also got the inner conversation he was having with himself and his memory of his ex-wife.
The supplementary podcast commentary that Moore put out is fascinating from a writing perspective because unlike nearly all the other podcasts he recorded for the show, this one was done basically covering his time in the edit room with his editor, and how they wound up piecing the episode together to "make it work," when they realized that as written, it wouldn't track as well on screen as they had thought. I can't recommend Ron Moore's podcasts for BSG enough, and this particular podcast episode for its dual value toward both writing and editing.
Kirk absolutely got it right in Wrath of Khan
-- "We learn by doing."