Wake and bake types always use this argument. So what if it's the bus driver's first time on THC? Just let them go for driving a full bus over a cliff?
I'm not anti MJ btw, but the logic is weak here.
MOST people who smoke weed all day are impaired in several ways they can't see. If it's "your medicine" to stay sane you shouldn't be driving for a living anyway, period.
What if it is their first time chewing tobacco? Drinking coffee? Marijuana isn't going to make anyone drive off a cliff anymore than nicotine. Users are more risk adverse and will actually drive slower and be more careful. No one is driving aggresively on marijuna it is not alcohaul