Jerry,
If a boat burys its bow with the spin up, the pole is too short. I have found from testing that the spin pole needs to be half as long as the spinnaker hoist. Also look at the Australian dinghys. These guys have been sailing/developing very high performance boats with spinnakers for 50 years. They know how to do it and they know what the proportions of the mechanical arrangement should be. Their poles are 50% plus as long as the hoist of the spinnaker and they lift the bows of their dinghys high. No more questions; no more argument. I'm convinced!
Bill