According to the original article posted somewhere here by Carl Sagan, that guy had some wild hallucinations. I guess you would have to say Carl Sagan agrees with Trout. Kinda trumps most anyone around here since that article was posited as being proof positive that marijuana is the end-all be-all of existence by the pot-heads. I sure want people driving who think colors have come to life and **** like that. Sounds EXACTLY like what every single person who has binged on coffee to stay awake to study for finals has experienced, except of course the opposite.
You have to be ridiculously stoned for that stuff to happen. Which I have been (and frankly, I hate it and never smoke enough to get that high anymore). And at that point I'd wager you wouldn't have the capability to operate a vehicle regardless.
That being said as a guy who wants to see it legal on a pragmatic, compromising approach I don't care if there is some low (not no tolerance...no tolerance laws are just dumb in general for anything) tolerance law against driving while stoned, being it measured by whatever.