I don't think they needed to go faster; they needed to convert in goal-to-go situations. Those two 7-minute drives would have been just what the Dr. ordered if they ended in seven points each. That second one, especially, would have been a perfect, back-breaking drive, with Sayin converting about three consecutive 3rd and 8s on the way to a bunch of time off the clock and 7 points.
It was obvious that Hartline had just about zero confidence in the offense's ability to pick up a yard or two with a handoff when the defense expected a run. That's a problem if he's wrong to have no confidence in it; it's a bigger problem if he's right. The only reason the slow-play, efficiency method wasn't a winner is that they weren't able to be efficient in goal-to-go situations. Maybe running some kind of hurry up inside the 20 would have helped, but if you simply can't run for 1-2 yards when the field is condensed and they're expecting a run, that's pretty limiting.