For me this is where common sense comes in. If you're caught without a fixed blade and what you want your folder to do could break it, DON"T DO IT!!
Lets face it, whenever you start to comprimise with any thing chances are it won't do any one thing well. Can you paddle whitewater in a touring canoe? Yes I have done it,,IT SUCKED! Can you paddle flat water in a whitewater boat? Yes,, THAT SUCKED TOO!! Now days, as it has always been, a specialty item made for doing one thing,very well, PERIOD. In a pinch do your best with what you have and there is no such thing as cheating when you are trying to stay alive. We as humans have risen to the top because we have been able to adapt and improvise.
I have cut green saplings 2" in dia. with my Opinel #8.Easily. Stand with the sapling under your arm and bend it as much as you can then cut on the side that is in tension. It comes loose pretty dramaticly. If you can't split wood in cold weather it's gonna be a long night. Deal with it or die, but don't break your knife it might be all there is between life and death.