for more than ten years I assigned some version of a pro vs con, usually on legalizing, cannabis in freshman comp classes. I read some funny stories but never once did a student ever say that they had been involved in a traffic accident as a result of pot. Quite a few reported having been stopped by police for driving too slowly.

but the bottom line is, if you are driving impaired you get a ticket or worse, just like with alcohol. There was never a reason to treat marijuana any differently in that regard.

I stopped at a rest area once and a gentleman came up to me and asked if I new what the speed limit was. I asked him if he knew what the minimum speed limit was. He just turned and walked away.
The only ones I may cause to have an accident are the ones driving 10 mph or more than the posted speed limit.

does not qualify as "too slow."

As soon as I'm drunk I can't walk straight my day is over. I'd never advocate for drinking and driving never. The more you use cannabis the less of an effect it has plus you can still pass a field sobriety test.

“One eyed driving.” I would drive after drinking many times, which is something I don’t advocate anyone doing. When I did drive after only using cannabis I didn’t need to do “one eyed driving.” I’ll say I’m very, very lucky to have 0 DWI’s. 😃

one assumes the constant dosing at a specific level would habituate them a bit to it.

Recreational pot? I'd bet they are less likely to WANT to drive--certainly in comparison to alcohol.