I've given this some thought and it seems I come up with a different answer each time. Here's where I'm at right now. A very difficult question. Especially given the lack of other information. I think we as americans, those of us here that are, suffer from the bigger is better complex.
The big choppers BK-1, BK-4, are cool, but they process game poorly. But they make great shelter builders.
The BK-7 is a great all-round blade, great at nothing, but will do everything. I think the BK-9 falls into that category as well. I don't have enough time with my BK-2, But I'm guessing it would fit in with the 7 & 9.
I love my Brute, but it would be a pain to skin a deer with. Remember, if you're surviving, you're going to want that pelt with as few holes in it as possible. You can "butcher" meat with a big knife, (it doesn't have to be pretty), just edible. But you're going to want that pelt in good shape. Rabbits and birds can be pulled apart. You haven't lived until you stand on a partridge's wings and pull on it's feet.
That being said the BK-1 and the BK-4 are acceptable makeshift drawshaves, Very cool for sustained life in the woods. I also looked hard at the BK-4, and BK-6, and here is what I came up with.
"Forgive me father Ethan, For I am about to sin"
Once I got my shelter built to where I was comfortable in the fact I was not going to die. I break that sucker right behind the wide part. Effectively giving me two knives. A BK-3 type and an improvised Ulu skinner. The back half whittles, notches, chops lightly, and has some self defense attributes. The front half does all the game processing chores.
I live in a hardwood forest in northern New York. Just for fun and out of boredom. I went out Monday morning and gathered downed wood for a fire. I stayed within roughly three hundred feet of my fire pit. I got to doing this after contemplating the "One Knife For a Year" thread over on the Ka-Bar Forum. Another thought provoking topic. The fire is still going. It dies down overnight, but only because I have not been stoking it after about ten pm. I have been able to rekindle the coals in the mornings.
I love to baton wood. It's like therapy for me. I get to beat the heck out of stuff and nobody cares. But in the woods, in a survival situation, I see little value in it. All the wood I have burned in the last three days was harvested with no tools. I broke it down to convenient sizes by beating it over my normal chopping block. What I couldn't break, I piled on top and burned in halve. I wasted some wood, as this was not for survival. I indulged in some chilled adult beverages in the evenings around my fire.
We discovered the long fire trick many years ago in while camping in the Adirondacks. I'd like to say it was gleaned from some wise method of bushcrafting, but alas it was not. The truth is we were either too drunk or too hung-over to hand saw our wood as was always the case previously. We just started feeding whole length branches that we carried to our fire. Once we sobered up, no one ever wanted to cut wood again. The long fire serves as a warmer if pots are placed slightly back from the main fire, It can be used for baking. It also delivers a frightening amount of coals for cooking. This method of cooking has provided us with such backwoods delicacies as Pheasant Cacciatore, Beef Bourguignon, and many others. Not to mention a lot of meat cooked right on the coals. All, I might add carried many miles on our backs and then canoed to our camp. Canoe was carried too.
As for self defense, wooden spears and bows have been killing thing for thousands of years. The key is to make them before you need them. I personally would worry about being killed by hypothermia, dehydration, malnutrition, or dysentery, in that order, rather than being attacked.
So my final answer is, I'd like to see Ethan's new drop point tweener (50 years in the making) that he showed in the video with the Machax before I make my final decision.
But remember, the Native Americans lived what I believe, was a very comfortable life with just rocks and sticks for a long, long time.
I got to go get some more wood.
YMMV
