Jim,
it depends on what exactly you want to get out of the sharpening process. If you use the Merlin/Harpy for cutting rope, gardening or "harvesting mushrooms", the exact serration shape and ratios (after resharpening) will not be of prime concern to you. In this case it is NOT much more difficult to resharpen than the serrated Endura, for instance. Just follow Sal's instructions on the MF204 SharpMaker video and you're there!!
However, if it's important to have the angle of the serrations correct with regard to the blade's curvature (needed for specialised applications), you need to take some extra time (and know what you're doing during the sharpening process!!)...
With regard to the tip strength: I feel that the Merlin/Harpy's tip might even be a bit STRONGER than the Delica/Endura's tip, because of the thickness of the blade spine in that region of the blade. The Delica/Endura tend to taper to a very thin point very quickly. I MIGHT be wrong in this regard, but I'll have a look at them tonight at home to make sure...
Anyway, in the self-defense sense (which was the thread taht got you thinking about these issues in the first place), the tip strength of the Merlin/Harpy is more than adequate, as the knife will more than likely be used for slashing, rather that thrusting (which is NOT impossible, but that's another story altogether
). I'd suggest that one modify the serration angle of the factory-model Merlin/Harpy a bit, to be perpendicular to the blade curvature at all points. The factory-models' serrations follow the same angle throughout the length of the blade, which is understandable when you realise that these are production knives. It will be very costly to do the serrations otherwise at the factory... Anyway, it's fun to do it yourself!!
