I'm amazed this thread has gone this far with such an in-depth discussion on cavities and Madame T'bird, Queen of the duble-enter-endre hasn't made an entry...
Welcome DrQ
(ps... never mention WWII, planes, tanks, motorbikes, tractors, sheds, small furry critters with big bushy tails, Hellcats, BoB, Indycar, Formula 1, the Euro and all things Greek, invading Poland [you started it!], Ze Kollecshun, lawyers-in-general [unless its very-very-ve-haf-vays-of-making-you-laff funny], mirror-shined leather, whips, TV, all general and obscure forms of perversion, Monty Python, especially all forms of Lark and Holy-Hand-Grenades... as you might never leave...)
Did I miss anything...?