It's no too often that you find a good BBQ Legend. But when you do, you best become good friends with that Old Guy. Bring him beer, bring him meat. Compliment his grill setup. Anything that calls attention to him wanting to grill for youis a smart move.
Speaking of smart moves... You might want to get him a proper BBQ Legend for him shirt to wear while he's grilling. Look at it as an investment in your own health and well-being.