I know it can occur, but nonetheless, an individual can be convicted of impaired driving even if they don't meet.... I think you said that. It depends on a person's levels. Somebody who never drinks and who then has a couple of drinks that put them at .07 is probably a lot more impaired than somebody who is at .10 but is used to drinking all the time.
That's just one of the indicators, and it's a separate section of the Criminal Code. I'm sure, as you say, that you can come up with examples in which the crown had a hard time prosecuting a case. Nonetheless it's still the law of this country that if you're impaired, you're impaired, quite apart from the other sections of the Criminal Code that specify that a certain level is an indication of impairment. Wouldn't you agree?