I know what you're going for, but I promise, you don't need to explain my writing process to me! Aside from occasional daydreaming, the 1-2 hours is really the whole writing process*, and I don't think it's reasonable to bill for daydreaming time any more than you get to bill for it if you happen to think of a research avenue to pursue at work the next day in the middle of dinner. If I'm consulting with another writer or sitting down working on outlines that's different, and that's incorporated in the "typical" time I gave.

The fact that you assumed there was another six to eight hours of research and plotting time is kind of my point, really.

*Unless it's research intensive, but the scenario I typically see people talking about with regard to commission work isn't "Let me write you a personalized history AU fic that incorporates the political ramifications of the Act of Union."