I can't quite see how that could be the case. If you ran the system as TN-C right up to the wall outlet, then had a 3-pin socket, you'd just link neutral and earth at the socket, surely, just as Ranger explained above. Why would this system entail the use of a fly lead from the earth pin on the plug?
Hmm...presumably to counteract the problems mentioned by Ranger. Sadly the ol' codger mentioned in the thread is no longer with us...he is polishing the tips of earth rods from below...
