I'm with Jay and the others on this. The wood is so rigid that stressful impacts that will result in flexing to a stress riser resulting in damage specifially at that bulkhead will just as likely result in wood/glass failure where the initial impact occurs. I'll try this differntly from my limited experience,,I built three s&g with hard bulkheads and two with minicell. There is impact damage on the Coho that results in fractured glass on the interior and exterior at various places around the hull. It has minicell bulkheads but the actual minor damage the hull has sustained is point impacts. The hull can flex and surprisingly the 5200 up in the forward bulkhead has pulled away from the bottom of the kayak,,sure a lot of that is water intrusion and possibly not the most thorough gluing job but I think some of it is actually from slight hull flexing. In other words if I put in a wood bulkhead it would be still sealed and I'd still have the misc. impacts distributed where they already are. The somewhat random nature of hull impacts requiring attention is more a function of the glassing schedule and type/thickness of wood. I could imagine that if I had rigid bulkheads, minicell bulkheads, hybrid bulkheads that were I to drag and lever a loaded kayak across a boulder that the resultant damage would be a function of the size of the cross section of the hull and glass schedules and not the nature of the bulkheads.