Okay, Matt, I think I have finally have gotten to the bottom of this. The problem with the Wave spinnaker kit is that either the pole is too short for the boat or the boat is too short for the pole.

In other words, it is a matter of the sheeting point for the spinnaker. Even if tacking downwind, the spinnaker backwinds into the main, because the sheeting point is basically as far back on the boat as the sheeting point for the main, and the tack of the spinnaker is not very far in front of the main.

So, either the sheeting point has to move back (and there is no farther back), or the tack of the spinnaker has to move forward (longer spinnaker pole).

Otherwise, when you are using the spinnaker, you might as well drop your main when going downwind, because the main is getting no flow and is getting backwinded and is creating a lot of drag.

Do I have that right? At least it makes more sense to me now.