First, there are SPOILERS below if you haven't yet seen Battlestar episodes "The Oath" and "Blood On The Scales."
SPOILERS. See the episodes before reading.
All clear? Great.
There's been some discussion in the ether about how shows evolve, occasionally punctuated with the criticism that the writers and producers are "making it up as they go." That meme strikes me as bizarre. Of course we make it up as we go, that's what writing is all about. In the case of BSG we always had a destination in mind, but there was plenty of room for inspiration and mid-course correction, based on a myriad of factors.
A small case in point occurred during the breaking and writing of the episodes "Oath" and "Blood On The Scales." While writing the script for "The Oath", it struck me that it might be interesting/dramatic if one of our main characters suffered a dramatic set-back in the course of the mutiny. The moment wasn't in the outline, but as I was writing I considered adding a beat where Col. Tigh was shot and badly wounded during the scene when he and Adama confront the Marines escorting them to the brig.
Sometimes on BSG you could just give this sort of thing a try, but blasting a character like Tigh had ramifications for other episodes (obviously), so I checked in with Ron Moore before actually doing it. He understood the impulse to up the tension and to create even more stakes for Adama, but he felt Tigh had been through so much (eyeball gouged out, poisoned own wife, discovered he was a Cylon) that shooting him would have been overkill. But the idea of having one of the final five seriously wounded? That idea stuck...
And so poor Samuel T. Anders wound up being "shot in the cabeza" (as the scene was described in the writer's room) in "Blood On The Scales." And that plot development... well, now we're getting into spoilers for episodes that haven't aired yet.
Anyway, I guess you could call that "making it up as you go", since there was no long term diagram mapping out these exact plot points, but regardless of when we came up with it, it wound up germinating and becoming organic to the story we were trying to tell. And if the entire season had been somehow "thought through" in advance, it may never have happened. I guarantee that Ron, David Eick and all the writers can point to similar moments of inspiration that weren't in any uber-plan but wound up taking us down interesting paths regardless...
And that's what makes the job fun! I would hate trying to write for a show where every little beat was etched in stone before I arrived. Coming up with this stuff is the exciting part!