"Do you turn the barrel behind you for speed?" IMO, bat/barrel speed is created by the combination of upper and lower body actions. It is not simply from TTB, although that is a part of it. If the barrel is not accelerating as soon as you launch, you are toast.
"Or turn the knob to the sky for adjustments?" I don't even know what that means. I have heard some HI/HLP followers talk about turning the knob to the sky, but more so in the context of a feel/exaggeration, that isn't to be taken literally. The talk revolves more around a 12/6 barrel path that tilts depending on pitch location. The fact that this "clockface" tilts automatically implies that "to the sky" is an over exaggeration.
Thanks FP! agreed! It is NOT the launch, but must be accelerating at swing launch.