"EU reform" is David Cameron talk: You will recall. And it has no place here after issue of the A50 notice by Tory gov and receipt by the Clowncil, accepted by Mr Tusk in fact.

Mr Tusk has said many things on behalf of the council, both conciliatory and trenchant, ignored here.

The A50 article of the Lisbon Treaty is remarkably brief and establishes one "right" for member states. That is to secede from the EU polity. It establishes a schedule by which the parties are to complete the withdrawal action. And it precludes the seceding petitioner's participation in EU polity determination of "Article 218(3) of the Treaty on the Functioning of the European Union."

So, yes. Having issued intent to withdraw, Tory gov is not able to "reform" EU political business.

The A50 does not further stipulate procedures for completing a member's withdrawal. Lisbon's signatories obviously did not intend to bind future EU legislators to such. This statutory omission instead compels future EU legislators to evaluate terms and conditions of withdrawal in each and every case.

The UK, being the first member to exercise its right, has created the first opportunity for the Clowncil and its agents to establish procedures for withdrawal. The effects of the procedures created by Tory gov's act will be referred to by future EU and member legislators as precedent.

Initially, there was some agreement among commentators here that the EU Clowncil had no incentive to mitigate terms and conditions of a member's withdrawal for fear of dissembling the union. I guess, you've change your minds now that you're (pl.) contemplating "sweetners" for Tory gov and speculating about EU-27 concerted affirmation of some right of a member to "revoke," or reverse, an A50 action, whether concluded or in progress.

That right does not exist in A50 or A49. A50 acknowledges an available prerogative to "rejoin" the EU. That statement articulates, commission of an A50 notice immediately conveys third-country status to the petitioner.

For A49 does not stipulate any unique procedure for application or "conditions of admission" for former EU members or politically amenable heads of state. As a practical matter, each and every application is negotiable But any future UK gov must conform and affirm establisment treaties of the EU as is (cf. Reconstruction of the Confederate States to the US Constitution) or negotiate a cherry-picking trade "deal" with EU gov.

Which is still, obviously, very much motivated to prevent dissembling of the union. No one will put the cart before that horse.

Diversity is the key to economic and political evolution.