I'm embarassed I did not give the issue enough thought to arrive at some of those conclusions myself.

One thing I do know, the vision we like to have of early Man as a mighty hunter may be highly exaggerated and largely self-serving. We probably got our taste for meat by scavenging the pickings of larger predators, or driving off hunters from their catch with our superior numbers (like jackals or hyenas or....wild dogs, all of which exist on the savanna!).

Canine packs and hominid bands possibly followed each other around and formed a symbiotic relationship. We utilized their superior sense of sense and hearing, they took advantage of our size and upright-stance assisted vision. When dogs AND men showed up together, even a big cat or a pack of hyenas might be persuaded to surrender its kill and withdraw. With a large kill, like a zebra, there might even be a surplus of meat available so there would be no real need for man and dog to compete for it--and both animals are smart enough to figure that out.

There is an existing analogue for this. African honey-eating birds have learned to get the attention of human honey collectors when they find a wild hive and actually guide them to it. The men drive off the bees, collect the honey, and leave the birds a nice dividend of honeycombs for their assistance.