If we assume that MJK was not the culmination of a campaign,the last act in some twisted plan, then why did Jack stop. Did he simply die or kill himself,was he imcarcerated on some other matter and kept the secret to the end.Personally while not entirely convinced by the identification of Carl Feigenbaum as Jack Trevor Marriott in his book does produce reports of Ripper style killings around the world shortly after the last episode in London, and i am prepared to consider the possibilty that JTR just moved away from London to carry on his work elsewhere, leaving as a seaman or passenger.