Doe, the problem with this and many such threads is we are pondering subjects with so many variables that we have little control over that none of us know much of what we are talking about. It's absurd to say velocity doesn't help. But how much? When? How does it work? What should a bullet do or not do for this benefit to happen? As for your case with the /06, the 270 and the 7/08.........you're talking about very similar velocities, diameters and I suspect even bullet weights. I assume you are including similar shot placement as well? It makes me wonder about actual bullet performance. How much did each bullet open up, blow up or otherwise react with the target animal?

Another factor that I've seen have great influence is what was an animals frame of mind when shot. A frightened or alerted animal is 10X more likely to run like hell after being shot than an animal peacefully grazing and unaware danger was anywhere around. Once they get charged up with adrenaline, they may as well be on heroin.