

It drops the graphics to their recommended settings, but you’re free to crank them back up to anything you want. No, it doesn’t check in any way. I have no idea why you would do this, it basically only means anyone who doesn’t check Proton DB for config advice will think the game is half broken.
Decimeters are almost always superior to cm. Like in this case, dots per decimeter is basically “If you drag your mouse across your mousepad, how many ticks did it record.”