Sorry bud, but your bias is showing. At some point we should be told the truth because if we are told something that doesn't correlate with our own personal experiences then we tend to disbelieve the authorities. 
(from the US National Institute of Health) THE EFFECT OF CANNABIS COMPARED WITH ALCOHOL ON DRIVING
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2722956/
In summary - Surprisingly..., most marijuana-intoxicated drivers show only modest impairments on actual road tests. Experienced smokers who drive on a set course show almost no functional impairment under the influence of marijuana, except when it is combined with alcohol.