So I got leveled up enough to beat the guard captain and I think I figured out why the QTE meter is so fast. When I beat her by reducing her health to zero the bar was much slower than when I beat her by removing her clothes with a few lucky Goods on dodging her attack (which mercifully did not care that I got Bad on the QTE 80% of the time). It looks like if the enemy has health remaining the QTE event is harder, meaning QTEs are harder on grunts and bosses if you go the sexy route than if you just attack a boss down to zero health.