The story of the two blokes in The Oak discussing it with the barman does have a ring of truth about it. Something very similar happened to me.
Was in a bar, and couldn't help overhearing a couple of swarthy guys talking amongst themselves, seemed to be Iraqi diplomatic staff from the sounds of it.
One said to the other " We can be ready to launch WMD's in 15 minutes"
The other replied " Excellent, we will give them the Big Smack they deserve"
I obviously reported the conversation to the relevant authorities, who apparently put it into some sort of "dossier", and caused quite a bit of a stir.
On reflection, I may have misheard them, think it was:
" We can be ready for lunch at Maccy D's in 15 minutes"
and
" Excellent, we will give them the Big Mac they deserve"
Wish i hadn't said anything now...