A cautionary tale about Lauan (sp?) ply:

I recently tried to bend 3/16" Lauan plywood for some window trim. It kept failing within the center ply, so I tried to soften it with hot water. It delaminated within ten minutes; you could just peel the face veneers away.

This was old plywood of unknow origin, so this experience may not apply to the stuff sold now, but if I was going to use it in a boat I would be sure to test it first.