Tim Hames in The Times reveals that Boris Johnson "implied he was a supporter of the SDP" as part of a plan to reinvent himself after an election defeat in the 1980s at Oxford University. It worked - so perhaps Boris should thank the SDP for launching him on a political career in the first place?
Hames also makes a fairly safe prediction:
Boris is incapable of maintaining discipline until next spring. A disaster of some form is inevitable. He will either be exposed as having, how shall I put it delicately, “leafleted” several female London radio newscasters, or something he once wrote insisting that citizens who travel on a London bus are hopeless losers will be unearthed. Or maybe he will turn up in Hackney and declare what fun it is to be in Henley. Perhaps all of these mishaps will occur simultaneously. The media, an industry where (unlike Papua New Guinea) cannibalism is rife, will skewer him mercilessly.