I sometimes use a Manfrotto 468MG Hydrostatic ball-head under a Tachihara 8x10 camera. It works fine except for the routine ball-head problem of making ultra fine adjustments. For these, usually leveling the camera, I tweak a tripod leg instead of fussing with the ball head.
The 468MG head uses tons of hydraulic pressure to clamp the ball. A light turn of the lock knob is all it takes. I reckon the metal parts of the head will snap before the ball slips.
Photography, the word itself, invented and defined by its author Sir John.F.W.Herschel, 14 March 1839 at the Royal Society, Somerset House, London. Quote "...Photography or the application of the Chemical rays of light to the purpose of pictorial representation,..". unquote.
No disrespect intended, but that set up David shows looks like broken fingers just waiting to happen! I agree, the B2 has a very fluid pan to it, but I can't imagine putting an 8x10 or larger camera on a ball head.
Have you used a B2? There are separate controls for left-right tilt and fore-aft tilt just like a regular pan tilt head, so it isn't like any other ball head that can flop in any direction. The balls are also slightly eccentric, so they increase tension as the angle increases to prevent sudden drops along either axis. Haven't lost any fingers yet!
I agree, though, that I wouldn't use any other ballhead with a large camera.