I don't really understand the common preference for fixed blade over folding knives. Yeah, I get that they're more durable ver the long haul, but if the intended use is to open the blade and stick it into soft tissue, (whether in SD or processing game) I don't see how a folder is inferior; it's not like I'm going to be trying to baton firewood with it.
I actually prefer a folder over fixed blade for everything, but especially in this context of concealment being the priority. If I'm not carrying a knife at all because I can't hide it, that fixed blade isn't very useful.
To start off with, I believe carrying a knife instead of a firearm, if a firearm is legal, is not a good idea. I have trained, frequently very hard, for almost 30 years, and even someone like me is generally better served with a firearm.
If you're going to carry a knife for defense, there are some things to think about. Some of these things may have already been mentioned, or mentioned in a little different way.
In general, folders are much easier to conceal than fixed blades. Law enforcement are also more likely to view a fixed blade with suspicion than a folder.
Fixed blades do have the advantage of being inherently stronger than folders. Also- and this is a big deal-
you should be able to use your FB with the same grip that you draw it with. Some folders force the user to change his grip after opening. (This is the reason, for instance, that the assisted openers I've seen are not good knives for SD. Every one I've seen requires a hand move or shift before being able to use effectively.)
Okay, pictures.
The Spyderco Native, I
could use immediately after opening, though it's even more secure if I rotate my grip slightly. It's a 3-part opening sequence: draw, thumb into hole, swing open.
(could cut fairly well at this point)
The Spyderco Yojimbo 2 is the right size and pivot location that I can reduce this to 2 movements, drawing and "popping" the blade open In a way that I can't with the Native. It's extremely fast. (The first knife I was able to do this with was the Buck Crosslock. Be careful, and build this ability up slowly and precisely. I saw a customer at a K-mart open himself up pretty badly trying to pop a Crosslock open like I could.)
(usable)
Again, at this point, the knife is in a perfectly usable pinch grip, though changing it to a traditional or saber grip would be preferable for me.
The large Cold Steel Voyager Dave Mc gave me is a different proposition. It's so long that opening is a three-step process, and I have absolutely
no control until I move my grip. So, even though it's more capable once in my hand and open then the much smaller Spyderco Native, it's much slower into action.
(no fighting control here)