I think bone is softer than aluminum. Maybe about the same as a hard wood like maple. You should have no problem with cutting deer bones.
Maybe what Carl meant by "you're going to mess it up" by cutting deer bones is literally the mess: blood and marrow between the teeth and in the joints of the knife.
As for sharpening it, I wouldn't worry. If it gets dull, send it to Victorinox, and I'll bet they'd sharpen it for free, since it is not a common tool that can sharpen that saw.
The Vic saws are VERY sharp. I closed one on my thumb one time, and had a bunch of little bleeding holes. Watch out that you don't get overzealous with the sawing, jam the tip on something, then accidentally close it up on yourself.