I am of course shaking in my shoes!!
Been thinking about why the notion that party membership selection the next PM is such a problem - I think it is because it runs counter to the convention of selection of a PM, who is effectively the lead of the group of elected MPs who are in a position to form a government.
So, of course, the best situation is that a PM is elected as the result of a general election.
But if not (as in this case where the PM is changed mid-term) then I think it is better that the PM is selected by the parliamentary party, in other words the MPs, who have a democratic mandate. To allow members (who have no democratic mandate) to make that selection seems to run against democratic principles.
So I'm more comfortable with the approach that resulted in May, Brown or Major (chosen by MPs without resorting to the membership) rather than the current approach, where the choice (unless everyone but Boris pulls out) will be in the hands of the membership.
I have no issue with the leader of a party not in power being selected by party membership because they will only end up as PM if they gain a democratic mandate, but not for selecting the leader of a party already in government.