I’d tickle the palm of his hand with my middle finger while doing a bone-crusher and grab his forearm in a Roman handshake while looking over his shoulder and smiling at a random person behind him, then walk off.
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Learned that move from my 78 yr old Italian-American NJ boss at a print shop in NJ. Throws them off and they never forget you.
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I’d be tempted to do the “slam on the shoulder” power move but that’s too abrasive and obvious.
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