Train rows are more interesting on your own line: there’s a certain intimacy and one knows the flashpoints. Mine runs through Essex and I have witnessed many a snarl in the Shenfield area and once stopped a drunken conga with one raised hand and an oath. Rowdy young men respond well to being sworn at by an old boot. It takes them back to primary school.

Normally it’s male drunks, so I was interested to follow the bizarre events of 18 months ago on the same line. Erika Stoter likes to eat a breakfast of smelly boiled eggs on Greater Anglia’s 6am service from Chelmsford to London Liverpool Street. One day in September last year, she opened her Tupperware box and was told by