Let’s not all get too smug. So a salesman does not know how a product actually works? Big deal. Let’s have all the regular forum members explain LEDs. See what I mean?
Who cares how water pump lubricant does its job. Maybe the antifreeze enters the bearing, bathes it. If this product can truly extend the life of a water pump, preventing emergency repairs, then it’s a good thing to have. Like those guys here who insist on using fresh synthetic oil every 3000 miles, why not? Can’t hurt.