A handshake is, among other overwrought and symbolic irrelevancies, your chance to exert some mano e mano dominance. You look the weasel in the eye and demand his limp, damp offering, you grab that foul thing and you give it a squeeze, not a big bone crushing grind that shrieks of overcompensation and a salvaged collection of mum's old dresses in your closet, but a measured squeeze, a firm no nonsense hand that says very clearly 'there's plenty more where this came from, fop' before you casually go about the business of not caring too much for your mealy mouthed and vanquished would be foe.
Anyone who refuses the opportunity has obvious issues. Issues that are no business of mine.