Try to imagine the scene at the front of the lines, as already overworked TSA agents are forced to take tape measures or rulers and gauge the length and width of knives, as travelers insist their blades are shorter than 2.36 inches or that they aren't more than a half-inch wide.
When buying a pen, he takes time to gauge how the pen feels in his hand the thickness, weight and length have to feel right or he may write more clumsily than usual.