Dan, <<My point is that the bond is not mechanical (i.e. there are bubbles
that get filled mechanically holding it) but is in fact chemical.>>
Unless I missed it, I haven't seen anyone mention PVA.  It forms a
physical barrier over the wax.  I use it on all plugs and molds and have
never had issues with sticking, even on materials such as Bondo.
 Chris Zavatson