What’s the most comprehensive contraction? Philip Cohen proposes this story:

An old salt was telling of going through a typhoon in his sailing ship. At the top of the storm, he said, ‘M’ jibs’l’s lines snapped. And m’t’g’ll’nts’ls’d’a done the same if it hadn’t slacked off just then.’

M’t’g’ll’nts’ls’d’a means “my topgallant sails would have” — a savings of 14 letters and four spaces using seven apostrophes. An old sailor knows the value of efficiency.