Bathroom Humidity

[jteneyck]

Curious about not gluing to a stable back.  I agree that is a bad idea with larger pieces...but 6"x12"should be easy to keep that from moving without bad side effects???

Well since I was the first to disagree with you idea I'll offer my 2 cents.  If you glue a solid piece of wood onto one side of a piece of plywood, it will almost certainly bow as the RH changes with the seasons.  The solid wood is going to swell or shrink, the plywood can't.  At the least, it will bow.  Worst case, the solid wood cracks or delaminates.  With something only 6" wide it may not crack, but I'm pretty sure it's going to bow.  
John

[JosephP]

Appreciate the feedback.  Certainly not looking for an argument - just sharing ideas.  My thought was that a piece that small (and thin) would be able to be held in place forcefully where larger pieces can't.  If experience has shown otherwise, then I'll bow to that experience.