Anyone ever use this? If so does it work? If I’m spraying I usually procrastinate enough I can follow my progress by watching the tire tracks in the weeds. To be safe though I overlap and have often wondered how much spray I waste doing that. Thought about trying the dye if it works and doesn’t stain the tank. I saw 2 varieties at our farm store. One blue and one green colored. Not sure what green dye would mark on green plants but thought the blue might work.