So far the resignation letters have been less than straight up about the motives of the resigners.
Tom's one says: "Your leadership has been visionary and remarkable" but "I no longer believe that your remaining in office is in the interest of either the party or the country.
How and why this situation has arisen no longer matters."
My view is the "how and why" is exactly what matters.
We need to know what the Brownite critique is.
If it is for subjective reasons - e.g. they just like Gordon more, or personal ambition, then it reflects on them as resigners rather badly.
If it is for objective policy reasons then we need to know what those are because they will help Labour members determine who to back in any future leadership election.
For instance, if the Brown critique is limited to wanting different or less public service reform (i.e. abandoning or diluting the choice agenda) then despite the recent mess I would be reasonably enthusiastic about Brown being given a clear run against the Hard Left.
But if the Brown critique of Blair includes his foreign policy then I reserve the right to go and campaign for John Reid on principle because I will not vote for any leadership candidate who wants to change the current line on the Middle East.
Tom can get away with saying "How and why this situation has arisen no longer matters. " His candidate for the leadership of the Labour Party can't.
Similarly, the "deal" as outlined very sensibly by Ed Balls in the Observer on Sunday, has always been an orderly transition. What is going on now is not orderly. If Brown doesn't act to put a stop to this then my take is he has broken that deal and a) Blair would be jusified in saying "forget it, I'm staying until the next election, you're already fighting me so you'll have to finish the job if you want rid of me" and b) Reid or Johnson would be justified in throwing their hats in the ring for the succession.
The ball is in Brown's court.