avrflr i'm sorry you cannot post a polite reply. I'm just interrogating myself, and never mentioned fuel exhaustion, but in a low fuel configuration, it might have been possible that the tank LP pumps were not able to provide the adequate fuel to the HP pumps...
As you refer to the small items found in the tanks, I would like to see how you explain that almost simultaneously, two different items would have reduced two fuel flows to two similar values on both engines...