Reaching a boil and chilling also add ample time depending on equipment choices.
I save time because it takes me 7 minutes to reach a boil in my E-Keggle and I save time on the chill, because I dont chill. It used to take me much longer to brew before I built a dedicated system that was designed to save time.
Good point. When I do run-off, it works faster to get to a boil, because I turn on the heat while it's filling up. It's close to a boil by the time the runnings are complete.