Using the banjo burner I never, ever used its capacity. I saw no point in sending excess heat up the sides to waste, so I adjusted the flame to efficiently heat the bottom of the kettle. The smaller burner is able to achieve a comparable flame, so what's the difference? I suppose if I'd been content to waste 30-40% or more of my propane I could have brought the water to boil faster with the banjo, but that's not me.
My brew days are set up the night before with water in the HLT. I wake up, turn on the HLT and then I have a cup of coffee, maybe a bite of something, brush my teeth, get dressed, crush my grain if I hadn't the night before and mash in. No lost time, there.
As to the boil, my BK burner's on during my sparge so the wort is being heated nearly to a boil by the end of my sparge. No lost time, there.
I'm not "waiting for the water to boil".