: But to put it coarsely: laminated is stronger, hollow is lighter. Shape
: determines the direction of greater resistance. Do I need decimals? Heck,
: no.

Better slow down a bit on the laminated-is-stronger bit. Laminated wood is used in construction because clear timbers of adequate size are not available. Paddles are usually laminated to minimise scrap, or to taylor the wood properties (light wood in the center, hard wood on the edges, etc.) I don't think laminating has any effect on strength per se, unless you cross laminate (like plywood) to prevent splitting.