Quoted from local news:
"Thibodeaux and a friend went for a sailboat ride on Sunday in Lake Pontchartrain, then decided to take a swim. Because their boat was not anchored, they lost sight of the boat. Thibodeaux's friend was found alive nearly 13 hours after crews found their unmanned sailboat."
The two were supposedly platonic friends The boat was found with the ladder down and towels on the rail, so it sure looks like they went swimming. But how the boat managed to get away from them is a total mystery, or a candidate for the Darwin Award of the Year. They didn't anchor, and didn't have a drag line deployed. The dude is 'sailing' a 40 year hull without a rig. Leaves fenders out. I assume lights off. Not super clever.