I find, if I come to realize that I'm at half mast, a quick trip to the loo to zip up can do the trick, worst is one is on the street or in a place with no facilities. In that case, one has to find a way to zip up as though nothing is wrong... dip into a corner... very embarassing anyway... how can one be cool about the discovery that one finds oneself at half mast. I shudder at the thought, I'd never walk around that way to show respect for a president, alive or dead, it just ain't natural.
Larry