You forgot (c) don't panic and abandon your current system as invalid just because it doesn't match somebody else's system. It's false to regard one system as

You forgot (c) don't panic and abandon your current system as invalid just because it doesn't match somebody else's system. It's false to regard one system as trumping another. We do not regard it as a breach in etiquette when someone eats in the "Continental" way in a setting where the American style prevails. The only reason to be embarrassed about the opposite is our American tendency to assume that European manners are more refined than our own, to the extent that we feel a little guilty when we go straight home after a soccer game without beating anyone up.