On another forum a Luthier was talking about caps/vaneers and from what I can gather it all depends on the thickness. "1/8"-1/4" thickness is deemed to be cosmetic and is unlikely to really change th tone of a guitar. He mentions that "1/2"-3/4"" is then 20 - 40% of its mass and at that point "tables start to turn".
_________________________
Guitars: Cort Earth Grand, Cort G250 RMS, Kimbara Strat Copy, Vester Strat Copy (Stage Series), Custom Build LP Style (By Steve Benford), 'Podcaster' Custom Build prize! (tele Style), Variax 600
Mac based recording and VOX AC4TV