Thanks Ed (and Q). I understand cathodic protection of ships as I used to work for a marine company. This "electronic" stuff just seemed like hooey to me from the start. But, as I had not read up on it, I figured it would be good to enlist help here at the Café.

The five year warranty on a vehicle less than five years old certainly is sommat to "do the math on". Seems like a money making scam to me unless there is evidence otherwise, but I just don't understand how it could actually work. And the website doesn't explain it.