Never heard of him. Might Google later.
Anyway, prodded a bit of solder wire into the socket, connected to the washer and mains, and LED went green before the power was switched on - clearly no diodes other than the light emitting indicator - so I took that to be progress as it meant a connection to the battery. Switched mains on and LED remained green for a few minutes before turning red. Again, took that as progress as I reckon battery is around 50% and would therefore accept a charge. Went out for a ride with my mates and, 3 hours later, the LED was still red. Took that as a fail.
Now given up and settled in with a cider.