The thing with hunting isn't so much about best possible scenarios, since it's true that you can probably down a lot of stuff with very little biles. The issue is just how little wiggle room you leave yourself with. If the bear's AI just spazzes and wanders off mid-approach to attack you, you miss a few attacks and suddenly you're out of yb/bb at low humours. Alternatively, they do spam roar sometimes (or used to). So while you can hunt them at lower humours it's important to know there's always the risk of getting KO'd due to a rubber-band or an AI spaz or a framerate drop.
As for guns I find they're not really that good for pulling as it's easier to bodypull or intercept their path if they don't aggro too fast.