Unfortunately you are all wrong. The correct answer is you do BOTH.
The words quickness and agility are not the first adjectives I'd choose to describe paddling a pedal kayak (like an Outback).
With my Outback, I paddle until i'm over the "first" major sandbar, then drop the pedal drive in while i'm over the second gut while I wait for the wave set to come through, then pedal fast as I can with my paddle in my hands to help out as needed.
It would be pretty unusual conditions to have to worry about hitting the next sandbar out with your pedal drive. Usually the "first" one is the only one of concern, and depending if it is low or high tide, the "first" sandbar may actually be the real first or maybe the second one.
Anyway, point is adjust to the conditions, but I usually will paddle first, then both pedal and paddle if I need.