For me, the axe versus knife issue isn't even the main dilemma - it's knife versus saw.  In my opinion, axes are too hard to control and too potentially dangerous to carry when I'm a few days hike from my car.  When I'm completely worn out after 10 or 20 miles on the trail, the last thing I want to be doing is swinging an axe around.  Plus they are heavy.
I doubt I would carry something the size of the dogfather, and I doubt I would carry an axe or hatchet, when backpacking.  If I'm going to chop, it'll be with a mid-sized knife.  Far more likely, I would have something like a sven saw.  A small folding camp saw might not be as fast as an axe, but it's a lot safer, and takes a lot less energy.  I appreciate that combination at the end of a long day hiking.