hey UG,
its probably a stupid question, but if u adjust the action on a guitar does that mean that u would have to reset the pickup height
Since pickup height is more reliant on personal preference (a few would argue against that) then no. You'll only have to change the pickup height if you think it made a difference in your tone.

Edit: beaten to it.
yeh but if u raise the action is gonna be higher at the bridge pickup than it would be at the neck pickup. So it would be on a slant (depending on the nut height) which would probably chance the volume balance between the bridge and neck
still prefrence, who know's maybe you want a volume differnce, so you can switch to one to do one technique that is harder to do loud, and just hitting the pick-up switch is easier then a volume knob or pedal. You can find a use for anything, even if it's not one you would use it for.