And go across the reef! I've had two owners do that because they weren't bright enough to realize the cartography on a chartplotter can be 1/4- 1/2 mile off. I've seen where the boat was going across dry land on the chartplotter screen, when I was in the middle of the ships channel in Key West. Heck, half of the time coming down the Tenn-Tomm it showed the vessel going across land instead of being in the middle of the river like we were.
I know a have dozen harbors, rivers and nooks that will put you on dry land following the chartplotters just in this area and it's wonderful. It keeps us working.
couple of weeks ago in Bimini i stopped a guy from getting on the shoal/reef in a Pershing 50... he was 1/4 to 1/2 mile off the channel, probably following his plotter...