OK, so on "what the fudge is going on" there's two great documents. The first is one by the Institute for Government that talks about the entire Brexit process.
https://www.instituteforgovernment.org.uk/publications/voting-on-brexit
The second is the Commons clerks' view on Grieve 2:
https://commonslibrary.parliament.uk/brexit/grieve-2-an-amendable-motion/
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If there's no deal, the government will present a statement to the House, then table a motion in neutral terms - "that this house has considered the statement by X" or whatever. Due to Standing Order 24b and the prerogative of the Speaker to not be, quote, cavalier, this originally meant to Grieve et al that the motion would not be amendable. Meaning no ability by parliament to block No Deal.
So Grieve et al got very cross and the amendment got pinged back from the HoL.
The government then went to the House of Commons clerks and asked "look, could you actually define what 'neutral terms' means in a bill".
The conclusion by the clerks was simple: even though a bill might mention or supposedly require a standing order to be or not to be in place, that has no legal impact.
I.e. even though the government can present a motion in neutral terms, the Speaker actually makes this call on if it is actually neutral. And if it's not neutral, then it can be amended. And this does not violate the Withdrawal Act.
But if the Speaker has to not be cavalier, how does he decide it's not neutral? Obviously it's worded in a neutral way. Standing Order 24b even says what a neutrally-worded motion looks like.
Answer: the Speaker could still decide it's not neutral, but they'd probably be triggering a major constitutional incident. This leads to cries by Mogg etc of "victory!".
Not so.
Any MP can put a motion before the house that could disapply (ignore) Standing Order 24b. If a majority of MPs in a vote then vote to do so, suddenly the Speaker can't decide if it's a neutral motion as that's been disapplied. Meaning suddenly a neutral motion is amendable.
But wait! Thanks to other Standing Orders, government business is conducted first, with everything else being pushed aside by it. This means that the government has to do what's called "making time" to allow for member's motion to come forward. That's what they're doing with Hobhouse's Upskirting Bill.
But this means
the government has to make a decision on if they want to make time for a vote on whether to disapply a standing order to allow for an amendment to a neutral motion following a statement made in the event of No Deal. This fudge is so big it is the only human structure visible from space. They will categorise it as one of the Modern Wonders of the World.
But anyway, they won't do that, will they?
Hence why the last paragraph of that Ministerial statement was co-written by Grieve:
"The Government recognises that it is open for Ministers and members of the House of Commons to table motions on and debate matters of concern and that, as is the convention, parliamentary time will be provided for this."
This means the Government, in writing but not in law, has committed to providing time for votes on "matters of concern" - like, for example, if a standing order should apply.
I said a few days ago that the most likely thing that would happen with the Grieve 2 amendment would be that Grieve and Davies come to a compromise to make a decision on whether the motion is amendable later. This is exactly what has happened.
The climb-down by Grieve is that he's allowed the government to have the initiative. They could go back on Davies' statement and deny time for a vote on the standing order. Which is why the exact parliamentary maths of the Grieve 2 vote was so interesting. Why did four extra Tories rebel when they didn't need to?
Simple: because it demonstrates to the government that there are the numbers - and there certainly are - to defeat the government on any and all legislation they'd need to do to bring about No Deal. Or, of course, vote the government down in a vote of no confidence, which would be justified if backstabbing occurs during an extraordinarily severe crisis like No Deal with three months to prep for it.
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"I think this meaningful vote stuff really begs the question, since it's not clear that the government could renegotiate anything. We'd effectively be putting an ultimatum to the EU to extend the A.50 deadline or have no deal if parliament refused to sign off on whatever deal Davis puts before them. It sounds like we're playing 3D chess but don't know the rules."
Hence why the meaningful vote being amendable is big news - it would instruct the government to take the deal the EU presents or extend A50. It shunts idiotic No Deal fatalism off the table.
EDIT: Fixed typos
