Doug, Just now after responding to Mike I read your two posts above mine. So the issue is what is the coefficient of energy transfer between the piece of metal (which appears to be brass) and the wood arm tube? Since Durand undoubtedly used a "hard" wood, and like substances wrt density usually present the least impedance, energy transfer may be good, or it may not be so good. Having only one bolt there does not suggest that one could attain a really tight boundary between the two, which would also facilitate energy dissipation. I am only thinking out loud here, and no slur on the Talea was intended. If Durand and his team found that this construction sounded best, and it seems they did, then I really don't give a darn about energy transfer per se.