Why would smaller hands be an impediment to double tap? You can adjust the levers closer to the bar on SRAM, which is nice I guess. Are you saying it's a matter if not being able to shove the lever over far enough to the side? I guess that's why test rides are important.

I like being able to scare flocks of seagulls as I ride by shifting my SRAM drive-train. That's important to me. Electronic shifting looks pretty whizbang though.