I have the same thoughts as Eric, although no technical data to back itup, particularly as it relates to boardless cats; in my case, a Prindle 18 but also the Hobie 16.

It appears to me that the bow area is fairly deep but as you move to the stern, there is a full, flat area that could easily promote planning. Inasmuch as I move backwards on the boat on the broad reach, and the bow does raise, I do feel that the boat does pop onto a plane. I can feel the difference as the boat "lightens" to the touch and gets slotted in. It's almost exactly the way my Laser felt when I could get that boat flying, and there is no argument that the Laser is easily a planning hull.

Sheldon
P-18 (sometimes planning!)