The reef could be handy if you get stuck somewhere and the wind comes up, and you've gotta get back. But we've seldom reefed the sail over the years.

The Nutshells are stiff as a stake because of the form of the full hull. I think you'd snap the mast or pull out the step and thwart before it capsized, as long as you kept your weight to windward.

Not so with many sailing dinghys, some go over in a flash.