Not my finest hour: I realized that I don't have quite enough clamps of sufficient length to clamp across the joint of every shelf in a bookcase I'm building. (There are eight shelves; I only have a dozen clamps.) The shelves sit in 1/4" dadoes in 3/4" plywood. Would it be sufficient to clamp across as many shelves as I have clamps for, given that each side is a single long board?