At a Laser event a couple of years ago someone put an FPV camera on one. The then European champion (who wasn't bad at driving a Laser) had a go with it. Took about a couple of minutes before he rammed the bank. From near water level, you get a totally different, and not always helpful, perspective on what the boat is doing.
Having a spotter might not be a legal requirement, but not having one really is a dumb idea. There is no idea of perspective, and zero conception as to what is going on around your boat out the camera's line of sight.