Well, a hawkbill blade would seem to produce a lot of drag as it passes through material. That would cause a ripping type cut rather than a slicing type of cut.
The ripping kind of cut a hawkbill creates would be useful for self-defense, as such a cut is probably extremely painful and would cause serious tissue damage. On the other hand, a clean slice cut is sometimes not painful at all.
The problem with a hawkbill blade is that all of that drag will make it harder for the blade to completely pass through the material it's cutting. The blade may slow down and could even stop in the target, or it could snag on harder parts of the target. Cutting through flesh is probably not difficult, but cutting through layers of clothing, buttons, buckles or zippers, and bone could present a big problem.
That's probably why you don't see a whole lot of hawkbill bladed weapons throughout history: they look cool, but there's the danger of them getting stuck or hung up during combat applications. If they're kept extremely sharp though, there's probably a lot less danger of that happening. Plus, if you're looking at a situation where one slash is all you need to make room to run away, then the danger of the blade getting hung up doesn't matter much.
One famous example of a hawkbill combat knife would be the kerambit. If you look at the kerambit though, you see that its design is totally geared toward dealing with the drag. They usually have very small blades (less than 3" long). The smaller the blade is, the less drag it creates, and a small blade will be less likely to penetrate deep enough to snag on bone. Plus, kerambits have a ring on the pommel that you can put a finger through for a secure grip. So if you do hit a snag, the knife won't be jerked out of your hand.
So, I think a Merlin might actually be
better than a Civilian for self-defense, because the blade's a bit shorter. However, the Civilian's handle is curved at the butt end so you can use more force to pull it through.
But that's all just contemplation and speculation and you shouldn't take it too seriously.
However, if someone out there has both of these knives, it would be really cool to see a comparison test and/or review on them. That would probably provide better info.
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Cerulean
"We cut things to create things" - J.K.M.
