Hugh,
I agree that the improved combustion technology you cite would not be unreasonable in terms of preserving the historical integrity of the D&S. It may be a better solution than the auxiliary heaters proposed by Earth Tech. That auxiliary heater system would require considerable R&D to develop the size, shape, and port direction of the burners, plus the manual handling and storage system, the ignition, the controls, the safety features, and the plumbing, not to mention the method of operation.
Earth Tech estimates that the system would cost $68,000-214,000. Assuming that several burner systems would be needed, I would not be surprised if the cost were ten to twenty times that.
RK