It is true that the poly or epoxy or rasin is just the binder; however, to find out how important of a role it plays do an experment. Take some glass cloth, lay it on a peice of thick balsa with a small peice of wax paper under one edge, then poly it down. After it is completely cured pull up on the edge that was prevented from bonding to the balsa. Though difficult you will find it will seperate. Now try the same thing with epoxy or rasin. You will find it almost impossible to remove it. Now keep in mind that the binder not only holds the cloth to the underlying structure but also to itself. The binder prevents compression of the weave or streaching of the weave. The material used for the binder therefore contributes to the overall attributes of the system of wood, cloth, and binder. A strong binder does add to the overall strength of the system much more than some might think.

Sharpeye