I've said this before but I'll say it again...the best defense against bears is to be careful with your route and campsite selection.  Stay out of areas known to have problem bears and check each potential campsite carefully for bear activity.  This is easier to do in Quetico where there are fewer problem bears and (usually) fewer problem campers who may have stayed at a site before you.

Beyond that, I prefer to camp on smaller islands (less reason for a bear to even bother to check it out, unless he's learned there is sometimes food to be had), out on the tips of long peninsulas with lots of open water around, and avoid necked-down areas where bears might choose to make an easy crossing of a lake.  Bears can and will swim, but prefer to walk.  Take advantage of that.

Other than that, keep a clean campsite, fillet fish away from camp, and seal up your food.  I don't have too many illusions about odor these days.  Odor-proofing isn't bearproof, but it can't hurt.

As you said, prouboy, whatever seems to work.  Proving a negative is hard..."bears can't find my food if I follow [insert your system here]".  It's like trying to prove Martians don't exist.  Just because we haven't seen any isn't any kind of proof at all.  

Study the "enemy" and know his habits.  Design your system around that, knowing nothing is foolproof.  It works until it doesn't work.  You're never more than 2 days away from civilization so you won't starve.  You just might have to end a trip early due to another of the many hazards in the woods.  

Life is a calculated risk.  It goes much better when you know more variables in the equation.