RE: RTR Hydro class rules.
As stated, the reason membership in a national organization is required is for insurance. While having an insured person would lessen the risk, if the driver messes up, runs ashore and hits someone for example, there's a chance of a lawsuit. Since most clubs promise the pond owner that they will provide insurance, they've violated the agreement. It's an unfortunate consequence of the times that we live in that any activity that creates risk, real or imagined, most likely requires insurance.