I strongly disagree. A great driver impaired by too much cannabis is not able to respond to the unexpected. Accidents are often caused or prevented by split second actions and being familiar with your car and a route to the extent that everything is second nature does not help you deal with the unexpected. You don't need to deal with too many nasty life changing fatalities to realise that cars are f*cking dangerous and driving needs our full attention. This is my last post on the subject but anyone who thinks they are as alert, possess good judgement and as reactive to danger whilst medicated are simply dillusional and lying to themselves so they can carry on doing what they want placing everyone else at risk. That's my opinion as a proffesional driver and experienced weed aficionado.
I think much of the issue - and debate here - is in your second sentence, "impaired by too much cannabis". What is too much? A few wispy hits of a light sativa from my Mi? 2 whole loads of a heavy indica? Vape up a whole gram of 25% THC bud before leaving the house? Somewhere in between? And, wherever that point is for me is going to be different for you or others.
I don't think anyone (especially me) has said they are as alert, or reactive to danger (though I would say many use better judgement) after a few hits. The question should be is someone alert/reactive enough for driving. Cold medicine can and does reduce both - usually more than any vapor. And, like most others a cold that requires some medication is not something that is going to make me call in sick. Lack of sleep, stress, checking out an attractive fellow driver or someone on the street, drinking my coffee, having to take a leak from drinking too much coffee, etc, etc, are all things that can and often do have a negative impact on driving attentiveness, judgement and reaction times. Of all the things that make my driving less than the stellar performance you and others are insisting upon, vaping might be in the top 5, but I doubt it.
A few months ago (and pretty sure I posted it in this thread about when it happened) I was having a VERY stressful week at work. As I said above, I don't vape when I'll be city driving or anything close. I stopped at a red light about 10 blocks from my office as I did at that corner at least a few times a week, was deep in thought about my stressful work situation, and blew through like it was a stop sign. Had done no vaping for at least 20 hours, and was totally sober. Needless to say, no one was coming the other way - like I said, I did treat it like a stop sign. But, I didn't even realize what I had done for a half block. Had I taken a hit or 2 before, I have no doubts that I would have been paying closer attention to my driving and certainly at least a bit less stressed. So, much less likely to make this totally idiotic move.
You may want to watch that "experienced weed aficionado" claim around here. I've got plenty of experience with weed (including taking all driver's ed in HS - right after lunch - much more stoned than I have driven in decades), but realize that's a very relative call. I'm sure there are many with more experience with weed than me (maybe even you), and many here who would make the claim even though they weren't even born until decades after I had smoked my first pound. At what point does either of us become an "experienced weed aficionado", and what is the relevance here? If either of us have more experience with weed does that make our points here more sound or true? I think not. And if it does, I ought to be getting points for it somewhere in here. I've taken T breaks here and there as needed, and have gone through years of sometimes weekly or daily use depending upon life factors, but I've been getting high for about 40 years and have a good bit of experience that doesn't even involve me getting high.
I've also been a professional driver and have logged probably close to a million miles over the years - mostly personal driving. I've been sober during any accidents I've been involved in, and while my reaction times have helped me avoid many others (while buzzed or not), they weren't enough to avoid being hit from behind while stopped at a light, or T-boned while having right of way in an intersection. FWIW I don't think either of those drivers were intoxicated in any way, either. Just lost in their own little worlds, as I was when I treated a red light as a stop sign.
And, herein lies my issue with most of this (repeated again from above and many previous posts in this thread). How can you or anyone else determine my experiences or levels of alertness, judgement, reaction times or anything else - after a few hits, a beer, or just pre-occupied? Especially to make such strong determinations on things to accuse anyone of placing others at risk or lying to themselves?
I hate this thread.....
Don't know why I still watch it....
It's so frustrating.....
Just causes conflict, and no one will ever agree on anything...
So just going round in circles upsetting each other....
Create conflict? Yes, it does. Is that a reason to not discuss? Many discussions lead to conflict of some sort or another - especially delicate ones like this. "...just going around in circles and upsetting each other"? Some, maybe. But, think many get a good bit more than that out of it. I know I do. I enjoy different opinions and perspectives. They allow us to see where we are on the spectrum of opinions of others, and maybe even learn a few things and evolve from our own viewpoints.