Gentlemen, I said the unit was design to go 15mph for transport. I didn't say it couldn't cut grass at that speed. The conditions have to be right for that to happen. If I said it can mow at 15mph everybody would expect it to cut 3" off without an issue. For those who believe the mower should not go that fast, there are limiters on the front dashboard to limit the throw of the sticks, hence lowering you max ground speed. Some owners de-tune the speed because of their workers.