An observation about plotting and pantsing. It's just my own experience, but perhaps it will resonate if not illuminate. And one necessary preliminary observation.
Prelim: not stated but usually implied is that plotting is not writing and that pantsing is. This may very well be true, or at least that they are two very different kinds of writing and that only the latter really counts--it's the writing of the actual story, after all.
A great deal of discussion is about the nature of these two activities, but we don't often talk about timing. Since I'm at the front end of my new novel, and since I have three others done, I think I can say I'm seeing a pattern. I start out planning. The amount and exact character varies and isn't relevant here.
At some point in the process, my planning starts to include me writing more than what kinds of animals live on this island, how a dragon flies, or whether my elf has blue eyes or grey.
I start writing descriptions. I write forks in the plot, just to see how each possibility might play out. I describe the friends of the MC. Most often of all, I write clips of dialog. Some of this stuff might wind up in a scene somewhere, some might not.
Just now, the Red Faction steps forward and says "see? you're pantsing!" and they might very well be right. But the Green Faction counters with "no, because see over here he has a file called Chapter One, and none of those fragments are in it. He's started anew, and all that stuff was planning."
What I've observed is that it's a bit like a teeter-totter (hey all you non-Americans, what's that called in your culture?). At one point the board is tilted all the way over to one side. It slowly tilts toward the other, and one day I wake up and I realize, hey, I guess I'm writing the novel now. But even when it's tilted all the way in the other direction, there's still micro-planning that goes on. (bouncing that teeter-totter was half the fun, yah?) Even far into editing, I might have to rewrite a scene or add a chapter.
IOW, there is no dichotomy here. We do both. We all do both. We do both in different ways, in different proportions, and these will change from one project to the next, at least over the course of our early works.
To put it still another way, if there were a clear answer, if everyone one said This not That, would it matter? Why not press forward with however it is you work, without regard for how others work? Sure there's a certain element of professional curiosity, but beyond that, it really comes down to what you put down when you sit down.
