You know what, I think you're on to something...
No one would suspect him!
Like my father:
Post 9/11 checks onto a flight from Saudi to the UK.
Puts hand luggage on through the scanner
Scanner beeps
Attendant's internal monologue also consists mostly of beeps
(my father forgot he left the traditional curvy knife with the 7" blade he got me as a present in there)
She looks up at my father
He smiles at her
She smiles back and just lets him board with the knife!
It's the mild well mannered ones...