Yep, I usually cancel out 1 for 1 -- it's a very additive & subtractive system (comparatively). Ultimately I'd say (with the benefit of hindsight/more play that's drifted) that looking at the fiction first ("which of these aspects is really the most important to model? impacts this moment most?") is the quickest/easiest bet, but there's a certain satisfaction from assessing all the details and letting them model what happens, too.
Nice. I’m glad that I was running it right. :)
I agree with what you’re saying about just letting the fiction decide which is most important. However, I think it’s also enjoyable that it can model one of my favorite things about Fate, which is the ability to overcome overwhelming odds (or at least dramatically lessen the damage) if you have a surplus of fate points (or in this reserve dice) to burn and narrative justification to use them. Both styles lead to a really different feel though (with the latter being more pulpy than the former), so perhaps it depends on the type of story you’re trying to tell at the time.