At some point in the fading afternoon light, you notice that your tongue feels like a crumpled piece of parchment paper. You try to summon enough saliva to coax it back into a familiar muscle, but the effort only further dessicates your throat. You pick up a coke bottle and it feels all too light in your hand. There's water in the taps but you know you're better than that. It doesn't have to be like this.
You grab the car keys and step into the driver's seat. Your palms feel clammy against the wheel, but the familiar clunk of the key turning in the ignition reassures you that this is all normal. It's just a quick run to the shops and it would take an idiot to mess this up. Inching out of the driveway, your foot eases off the pedal as you picture everything that could scupper your passage to a beverage. Congratulations, you're driving and you're high as balls.
Luckily for you, me and every other person who managed to cop a driving license while maintaining a casual marijuana habit, a new study has found that driving while blaaaaazed is kinda sorta not that bad. The laboriously named National Highway Traffic Safety Administration has found that being baked behind the wheel is better than being drunk. When you smoke, there's no significant increase in the likelihood of an accident. After a few beers, it increases seven fold (!)
If I were you, I wouldn't take this as permission to pull doughies in the Asda parking lot before you waltz in to buy some cereal. However, you may now feel a little less paranoid as you cruise down an A-road at 10 mph under the speed limit.