I've heard that spraying PAM on decks is an urban legend. I tried several products by a company called ZEPLON that was purported to be a teflon-based "dry lubricant" on my previous Craftsman lawn tractor's deck when it was brand new.....worked for a while but no joy:0(
To use "real teflon" you need to have a contract with Dupont as a Licensed Industrial Applicator(costs major $$$). Yeah, it seems like they would have come out with mower decks with a teflon coating(or maybe Emron....airplane paint) where grass dirt simply would not adhere but alas that's not a priority(or expense that could feasibly be passed on to the consumer) by ZTR manufacturers. I think you'll find that the PAM doesn't protect against buildup after a few sprays:0(