I don't think it was just BEA. A friend who worked at EGCC recalls a dispatcher going onto the flight deck of a BOAC VC10 with the request "papers to sign skip, please". The autocrat in the LH seat simply didn't register the presence of the redcap at all.
"Skip, papers to sign please". Again, totally ignored.
After the 3rd abortive attempt by the dispatcher to get the P1 to acknowledge him, the P2 turned to the redcap and said "I think the cu*t's waiting for you to address him as Sir".