My approach has always been guided by on question:
Are the bears here afraid of humans?
When I go to Algonquin, I hang my food - with a rope between two trees where necessary - and do my level best to follow Cliff's method. When I go to Wabakimi, not so much. Bears in Algonquin, or in many places in the boundary waters, very quickly associate humans with food. Bears in Northern Ontario turn and tuck tail at the first sight of humans - especially in areas where they're hunted.
It's almost blasphemy to admit it, but in some places, I sleep with my food in my tent. An unhabituated bear's fear of humans is more powerful than its love of food, at least in my experience.
I'll use a bear alarm composed of pots and pans and percolators piled on top of a food pack in many situations, especially in the boreal where there are no suitable trees. Other times, I'll use a rope strung between two trees with a rudimentary block&tackle made out of caribiners.
My great bear story is on the Missinaibi, at Peterbell. My general routine on this trip was to wake up, eat breakfast, throw everything into the tent after scouring my site for anything I left out, and then to pack up whatever I threw into the tent. Well, on this fine morning, I had thrown everything into the tent, and felt the need for a #2 bathroom trip. So being dutifully polite, I paddled to the other side of the river to do my business. As I was taking a glorious poo on a log there, pants around my ankles and enjoying the morning dew and sunlight, business half done, a bear wandered into my campsite. It ripped through my tent, picked up a 50lb drybag of food, and began to wander off.
I interrupted my morning constitutional, coming after this bear like a parent chasing a runaway petulant child. Paddled across the river in soiled pants with this bear still rummaging through the tent. I beached, picked up a paddle, and started charging this bear with neither sense nor intelligence, swinging my paddle like a madman. In my mind, I was going to beat this bear into submission. In the end, it ran away, after tearing through my tent and taking off with my food. In two minutes, I was left with neither food nor shelter. (The story of my extraction is also entertaining, but it's a long story.)
So back to my original point - my food security is governed by "
How afraid of humans are the bears here?". When I go alone, I make sure to have the ability to make a lot of noise, very quickly. When I travel with companions, I try to remind them that while a bear might not be afraid of
one of us, it will be
very afraid of four of us advancing upon it with military precision. Sometimes I carry lethal countermeasures, but not usually.
And if you haven't read it, I highly recommend
Bear Attacks: Their Causes and Avoidance, by Stephen Guerrero. It's both transformatively informative and hilariously entertaining.