"I have flown the 747-200, 300 and 400 and am not aware of any such problem with the landing lights;"
So this means it doesn't exist, Boofhead?
The latest info I have is that the PSEU (Air/Ground computer), on power down, has the possibility of latching in either Air or Ground mode. Latched in Air mode, the PSEU will put the lights on dimly when the aircraft is powered by the Ground Service Bus.
Being a pilot, I doubt very much that you've seen a -400 powered by the GSB ... and would probably complain if it was.
Q.