Agree with some of this, CJ, but there are several known "unknowns" to be taken into account also --
= The leave vote could be split between tories and the Brexit party UNLESS they agree to a non-aggression pact before the general election
= Labour has already committed (so I've read) to offering a referendum vote if it wins the election. This will lose it a lot of Labour north/midlands voters who voted to leave -- but maybe not enough to totally damage its chances (a hard core of Labour voters will never vote tory).
= Some remain voters who might have voted Lib-Dem had it been the only choice will vote Labour, now it's offering a referendum. Also, I think a lot of the tory/lib-dem coalition baggage will come back to haunt them in a no-holds-barred general election. People haven't forgotten the betrayal of Clegg & Co.
= If the Brexit vote is split (see above) this could leave Labour as the largest party without an overall majority, which would then have to enter a coalition with the SNP and various odds and sods to put Corbyn into No. 10.
= Then the fun starts. Corbyn would have no choice but to honour his pledge to have a referendum. Whatever the outcome, leave or remain, will bring chaos.
ps: there are also any number of unknown "unknowns" that no one knows about which would render the above scenario as redundant.