The drug test is a complete nonsense in my opinion. They need to be working on a much better test. At the moment, if you haven't smoked it in over a month, there is a still a chance you'll appear positive on a drug test. This is ridiculous because it's not testing whether or not you're on drugs at the time (I.e. during work hours), but whether or not you have done drugs in the last 4 to 5 weeks. This is ruining some peoples lives because medicinal users (or indeed the occasional recreational user) are losing jobs, or being denied jobs because of that fact. It's like being fired for having a drink in the last month
I guess you're right - Whether it's legal or illegal to smoke it, people who drive on drugs will do it whether it's right or wrong.

I think it's totally irresponsible though, and it is quite a scary thought...
I disagree (to an extent...) - People who smoke (While it's illegal) will drive on drugs whether or not the drug is legal or not. If it was made legal tomorrow, you think pot smokers will all go "Sweet! Let's go for a drive!" - Anyone that has that mentality, is already on the road, breaking the law.
Unfortunately, if it was legalised, the number of users would go up - Maybe not hugely - but enough that there will probably be a slight increase of drug drivers.