I definitely don't advocate driving high but the comparison between high and drunk driving are almost incomparable other than the fact that they are both intoxicants. People who are drunk can barely walk straight, let alone handle a 4000 pound automobile in a legal and safe manner. Apparently a couple drinks is enough to take out a whole generation in a family on the road...
I've seen high drivers and to be honest they're very careful. They for the most part go the speed limit (they think they're going faster when they arent) , respect the laws of the road, drive in a safe manner, stay between the lines without swerving etc. Honestly if you ever see a high driver, they are full out concentrating on the road, head straight, both hands on the wheel and full concentration.
If you ever see a drunk driver they are barely able to hold their neck on their shoulders...
Again I don't advocate for this because I'm sure they wouldn't fare well in an emergency situation, but the two are completely different and if I was forced to deal with one of the two I'd deal with the stoned drivers. As long as they stay in the right lane doing the limit, it's an open road for me.
My point Is, most people who are high can actually drive, most people who are DRUNK THINK they can drive as well as they think they can dance while under the influence.