the problem with this and the Guardian comment, is that it rest on some considerable assumptions. not least that Boris did all this soley to take over the role of PM, one his is not suited to given his maverick nature. he is suited to having some power but not responsibility, like London mayor. the whole piece only makes sense if Boris and Gove didnt really want to leave, that they campaigned for a cause they didnt actually want. seems a bit incredible.
i do think they may not have believed they would win as the polls even when prdicting a leave win had as much as 15% or so undecided so werent very comfortable leads. so they've been caught by surprise and hadnt really considered the actions required in the following week. they probably expected Cameron to at least stay around until there was a call for him to leave, again unsettleing peoples calculations. Cameron hasnt made played a cunning strategy in announcing to resign either, he's on type doing the honorable thing. recall the lost vote over Syria, he didnt actually need parliament vote to send in the RAF, but honored the descision. he simply doesnt want to do something he's argued he didnt want to do.
You are ignoring Johnsons huge ego, and public schoolboy sense of superiority. He also didn't expect to win, or come anywhere close, but as a gallant loser, he would have helped Cameron restore Tory party unity, and become the darling of the party. Acshoo in for Cameronscjob when he finally quits, and a public referendum defeat to put the Tory party eurosceptics to bed.
Job done