I have a Ka-Bar. I love it. I keep it so sharp I could shave with it, and yet I could chop down a small tree if I wanted. But I have only carried it backpacking once. I find I never need a blade bigger than my usual 3" folding pocket knife.

I do carry it hunting, though I confess it would be of limited use for processing game. I carry it mostly because I use Vietnam-era webbing for hunting, and the Ka-Bar looks right at home on my belt along side my other pouches and things. But that's a different application entirely from lightweight backpacking.

For backpacking, I don't know that you'd ever need anything so big. I mean, maybe if it was on my belt and I was attacked by a bear, then perhaps it might be nice to have a blade at hand, but even then I think I'd probably end up just cutting myself in the chaos.

Then again, it's your hike, so do what makes you happy.