My experiences with arms are that damping arm tubes smears the sound. I have removed all the damping from many arms both pivoted and tangential tracking and in every case it released significantly more detail, though in some cases a lightened quality to the sound my not suit some people. Often VTA was often set incorrectly to compensate for the damped, slugged sound.
As stated above, at every connection and change in material there will be both transmission away from the cartridge and backward reflection of energy back toward the cartridge.
So you can either sink the energy to ground through careful design and use of successive materials that encourage more energy to travel away from the cartridge and less backward reflection and/or use materials that dissipate unwanted energy, examples would be carbon fibre, which can dissipate energy as heat.
Damping tends to store energy and then release it later in an uncontrolled or out of phase manner, thus smearing the sound, eg rubber.
My gut feel would be that wood behaves more like a damped armtube than one that dissipates energy.
Unless you are using different woods to optimise the effective mass of the arm for the cartridge I cant see that its use is anything other than a tone control.
As one who has just come out of the timber industry I can assure you that no 2 pieces of wood will sound the same, even from the same part of the tree, if they do, it is a fluke.
