Damnit, I've commented on three different posts about wave-piercing hulls today and can't remember where the relevant stuff was to transfer to this discussion.
Generally speaking, all waves are the same, energy moving through a medium.
The bow wave however is going to be stationary relative to a constantly moving hull, so the energy "in the wave" isn't working against the hull, but rather the hull is generating the wave which takes energy. This is where the design of the bow needs to try to minimise bow wave generation.
Wind and ocean waves are still energy moving through a medium, but relative to the hull, that energy is generally coming towards the hull faster when going to windward than when going downwind (if overtaking the waves). These are the waves you want to have minimal effect on your vessels speed and seakeeping. An investigation into the natural pitching frequency of a cat hull relative to wave incidence period (which changes with boat speed and heading) would be interesting.
I'm not completely up on wave mechanics though so that's the extent of my wave discussion.
Don't forget this is all relative to a fast moving hull. Slow speeds will have different things to worry about.
My opinion why cats aren't built as true wave piercers, or why I won't design one as such, is because wave-piercers stereotypically have very small waterplane areas towards the bow. This means that under the influence of a pitching moment (from the rig in the case of sailing boats) the hull has to submerge further than a conventional hull shape at the bow to oppose this pitching moment. Not a problem if you expect minor pitching moments, but rigs can generate huge pitching moments...who hasn't pitch-poled one of our cats? There are other forces acting in the case of a pitch-pole, but I don't wanna go there today.
However, there may be other benefits to current "wave-piercing" like bows for fast beach cats. Mainly reduced windage upwind and reduced radius of gyration (because weight is taken away from the extremities of the boat). Maybe we should call them "wind-piercer bows" instead?
