I hunt.

knife? no - silly idea.

blaze orange during the season. Yes.

Just like we find idiots on the trail who don't respect anything, and they are the minority in our community, they exist in the hunting community too. Any decent hunter will never take a shot unless it's safe, and they're sure of the target. Unfortunately that doesn't mean there aren't idiots out there. I wear blaze orange or red in hunting season. you
don't need to be covered but a good swatch of it somewhere on you helps. A red or blaze *hat* is actually the best thing.
better safe than sorry.

Now having said that, the AT is a pretty established trail, and I would expect anyone hunting near it would know what's going on, and would not be "surprised" or "unpleasant" about having hikers in the woods with them. On the whole I think you're probably in more danger driving to the trailhead in your car than you are when you're on it.