Thanks for the update, Dave.
Remember, though, that in considering HBU, you have to consider the reasonable likelihood of change. The book says "zoning" change, but I think that might apply in this assignment, too. (Comments, guys?) Those "gentlemen's agreements" can get formalized quickly enough if it's advantageous to the parties, especially when all three owners share the utility--and especially among pilots.
But I'm afraid I may have misled you when I said 1700' would accommodate "most light aircraft." It will accommodate the smaller ones with ease, but for the ones which are good for traveling, like the 182 Mike mentioned, the Bonanza, Piper's Lance -- all reasonably fast cross-country planes -- it will depend on the pilot's skill and currency level, and desire to land. I once put my Bellanca Viking into a 2000' strip with room to spare due to very high hydraulic pressure. Took me 10 minutes to finish watering that grass. With only 1700' available, you'd be at the edge of the envelope for the faster light planes. As Mike said, you wouldn't attempt such a landing except in an emergency.