Some folks just like a spare blade, and there's nothing more to it.
I didn't understand Muskrats either, but I think I've figured out a reason for their existence, or rather a couple reasons:
- No matter how one pulls the knife out of one's pocket, the first blade one grabs is the long clip. One never has to turn the knife around after pulling it out to get the blade.
- Since there's no penalty in thickness, and very little penalty in weight, why NOT have an identical second blade, if that's the one you like?
- Lots of us use a large clip blade for 90%+ of our cutting. So why not just have two of them, and there's a good chance one will be super sharp when needed?
In my recent poll about Slimline vs. regular trappers, one person said he uses the spey blade for just about everything, and holds in reserve the sharp and pointy clip blade. That also makes sense. Over multiple sharpenings, I find it hard to maintain the sharpness of the tip of the clip blade. So if one holds that blade in reserve until one
really needs the clip, that won't be a problem.
That said, I tend to go with the majority here. I either like a single blade or two different length blades. I tend to use the large blade (usually a clip) for just about everything. The small blade is a back-up that is always sharp, and one with which I can accomplish precision work due to the shorter length.