Your concerns are understandable, that's why we recommend only about 1-2 turns at most
And JOYRIIDE1113 above gave excellent instructions on how to aim the headlights properly.
We would all do well to follow them to avoid annoying oncoming drivers.
Re: SUV's with blinding xenons.
IMO, the worst offender is our own BMW's X5! Man, I really hate it when one of them is stopped behind me at night, or worse yet, coming towards me! I try to look away, but I end up looking at them in the process of trying not to look at them! Then, for the next 20-30 secs, I'm like seeing these green afterimages burned into my retina!
Is there a website somewhere where we can put our complaints to BMW about the X5's xenons?