Drive to suit conditions, pay attention, brake in such a manner as to preserve your own ass but also when reasonable give your passengers a comfortable ride plus the comfort of not wondering if you are going to hit the thing they see looming. Also I brake in such a manner as to most clearly communicate intentions to people following. Tapping a few times might send flashing signals that wake up the maybe half-dazed brain of the person behind me. Slowing in “bursts” vs just coasting over an extended distance or slamming all at once seems to also be a good way of doing it.
If I had to choose an impairment a driver would be under, I’d take the high one over the tired or drunken one. I’d take tired before drunk, at least a bit of adrenaline or other stimulation might coax the brain into clarity as needed. But I’d rather ride with the one who is alert, but also drank one beer at dinner, before I go with the one barely awake.
Obviously allowing no willful impairment is the only proper way but it’s sometimes hard to stay 100% proper and we have to accept our levels of uncertainty and risk with each new challenge.
I’m in favor of getting rid of my cars and relying on transit going forward, to be quite sure.