I have one lens I bring to bear to view all theories about BF. It is one that I hope helps to see what a super-adapted bi-pedal animal is capable of doing in its native environment. The gold standard for comparison are the skills and habits of the N. A. Native cultures. We know some how these peoples earned a living and defended themselves from aggressors, but I'm assuming large amounts of information were lost, given the limitations of an oral tradition and catastrophic disruptions to their cultures. As well, we have to assume there is information to this day that is not shared with members of the dominant culture.
Even based on what we think we know about their abilities, there is a common agreement the N.A. Indians were supremely adapted at exploiting their environment to sustain themselves and avoid dangers. Just their ability to resist everything the continent could throw at them for 13,000 + years is proof of that. That they could not withstand the onslaught of microbes and guns just makes the case of their specialized adaption.
My assumption regarding BF is they are exponentially better at living where they live than even the pre-Columbian natives. One reason being, I believe, is they don't have the burden of sustaining a complex social order or maintaining even a rudimentary, albeit portable, shelter. It is exactly this pure nomadic adaptability where they do the N.A. Indian one better. As far as I can tell, for a BF, home is where the food is. When there is no food, "home" goes looking for more food. And over how big a range is this foraging area? "Frickin' huge", is about the only way to describe it that gets the point across. How good are they at locating and securing food? At a level that defies human comprehension and belief, probably.
So, on the topic of the OP, your are left to consider one more area of behavior for which we really don't have a known model. As I said before, you can tilt over into making the case for BF exceptional-ism, and open yourself up to cheap shots from those opposed to the very premise. Fair enough. But...if you proceed from the premise they are living, breathing, eating, crapping, breeding, fighting, sleeping, walking organisms, you've got to hypothesize how they keep on doing all of those things more often than not.
For lack of a better, more detailed explanation, I just have to conclude they are just very good at what they do, on a level I probably couldn't comprehend even if I witnessed it up close and personal. At a certain point, supreme adaptation looks like magic, and plenty of cultures are guilty of that misunderstanding. Not a very satisfactory explanation, but one the evidence is telling us to consider.