There is no way to make a tory-BXP pact work. It looks like a no-brainer, until you get into the details. Which seats are the tories going to stand down in to let the BXP win? Surely Johnson isn't going to offer Farage any seats he thinks the tories could actually win, right? Which means Farage would be asked to stand his candidates down in nearly all the seats that look most attractive to the BXP, and in return all they'd get is the tories standing down in Leave-voting Labour seats in the English north and midlands. But the problem with that for Labour leavers in those seats, the Brexit Party will then be indistinguishable from the tory party. Functionally, there will be no difference. Voting for Farage will be just like voting Tory.

The rest of politics doesn't just stop. Those people want brexit, but they also want a Labour government, and they absolutely do not want to be governed by a tory party that has just lurched to the right. They are happy to vote for Farage only so long as Farage remains a one-trick pony. The moment he becomes a de-facto tory, the game changes again. The Brexit Party will struggle to win any seats at all.

He wanted either a post-brexit election, or an election before October 31st. That was the grand Cummings-Johnson strategic goal - set up a situation where they get either one of those things or the other. But they made the mistake of assuming that Corbyn wouldn't be able to decline the invitation of an election, even though there's no tactical benefit for Corbyn to go along with this plan. By refusing, Corbyn looks like he's the one calling the shots, and forces Johnson to go and grovel to Brussels for an extension he doesn't want. Then he will lose a VonC.

I personally rather doubt that. You're assuming TBP can do a pact with Johnson and still operate in Labour-held leave seats as if they were a fully independent Brexit Party. But they cannot. As soon as there is a pact, TBP will just become an appendage to the tory party. Labour leavers will be very reluctant to vote for them. I think Farage will have trouble winning any of those seats at all.

OK...first comment from me. I am not a tory, but I am trying very hard to understand what has just happened. It looks to me like faced with a logically impossible problem, the EU and UK have just jointly agreed a solution which contains a blatant logical inconsistency.

[quote]
5. Under the caveat that nothing is agreed until everything is agreed, the joint commitments set out below in this joint report shall be reflected in the Withdrawal Agreement in full detail.
[/quote]

That includes this "agreement". Therefore no deal is still possible ("nothing is agreed" = no deal, hard brexit).

[quote]
43. The United Kingdom also recalls its commitment to the avoidance of a hard border [on the island of Ireland], including any physical infrastructure or related checks and controls.
[/quote]

Weasel words supreme. Imagine you are agreeing a divorce and you say "Yes, I recall the day I said 'till death do us part'". Recalling that you made a commitment is not the same thing as re-affirming it. A hard border is still possible.

[quote]
46. The commitments and principles outlined in this joint report.... must be upheld in all circumstances, irrespective of the nature of any future agreement between the European Union and United Kingdom.
[/quote]

This one looks incomprehensible. How can "the commitments outlined in this report must be upheld in all circumstances" be consistent with "nothing is agreed until everything is agreed"? But it is about avoiding contradictions in future deals rather than in the situation where there is no agreement on a future deal.

This is the humdinger though:

[quote]
50. In the absence of agreed solutions, as set out in the previous paragraph, the United Kingdom will ensure that no new regulatory barriers develop between Northern Ireland and the rest of the United Kingdom, unless, consistent with the 1998 Agreement, the Northern Ireland Executive and Assembly agree that distinct arrangements are appropriate for Northern Ireland. In all circumstances, the United Kingdom will continue to ensure the same unfettered access for Northern Ireland's businesses to the whole of the United Kingdom internal market.
[/quote]

Outright contradiction. How can "in the absence of agreed solutions then X" in paragraph 50 be compatible with "nothing is agreed until everything is agreed"?

Logically it boils down to this:

1) If there is no agreement then nothing is agreed.
2) If there is no agreement then X is agreed.

1 & 2 cannot both be true at the same time, and yet both the EU and the UK have agreed to both of them.