yeah John Deere used to put them on their "new" mower decks way back in the 1990's and early 2000's. I sold Deere (and quit them in 04), it was a gimmick is all it was. Frequent deck bearing replacement, rusted decks, etc. Water will combine with the junk that breaks loose of the deck and as the blades are running it blasts the blades with dirt/debris/sand/etc which wears the blades down, so the warsh port turned into a way for the service departments to make more money in the form of bearings, spindles, deck shells, blades, decals, whatever. THAT is why Kubota doesn't use them. They're simply not needed. Once a year I pull the deck out of mine and scrape it out, though, it's not usually that dirty. I just do it as part of winter service. I do it at work too. Some folks just have to mow regardless of the grass, and apparently some mow the ditches and ponds because I see mowers with under 100 hours on them and the blades won't even turn because they're so caked up with junk under the deck. Those take a little longer but people pay good money for us to service their stuff and I feel like they outta get their money's worth so I scrape them while on the lift. Besides a lot of times the blades are completely SHOT and then putting new blades on will rub against the buildup under the deck and if it's not cleaned out it can ruin a PTO clutch, belt, or best case scenario the customer comes back & gripes about "noise" from under the deck, at which point my labor becomes free for not checking the debris buildup. I got bills to pay too and free labor doesn't pay bills, so prevention is key.