So I'm in the process of putting together a driver/shaft combo for next season.

This is a pretty general question, which I'm looking for a general answer to. I know a fitting is always the best bet, but in general, why would someone go with an 80g shaft in a driver over a 60g, or 70g shaft? The tip flex seems to be a lower number as you get heavier, but the bend point, spin, and launch characteristics are all shown to be the same. I specifically speaking about the Fujikura Motore F3.

Thanks for the help.