The ground rules of diplomacy are no different from the conventions of society, writes Schadenfreude, our secret columnist in Brussels.

You say the right thing at the right time. If either is wrong, failure.

Think of the demand that under revised calculations some Member States of the European Union should pay more into the budget and some should receive a rebate.

The calculations are based on a new composition of national income, the basis of which was agreed by the Member States. They supplied the revised data. The European Commission applied the rules and came up with the conclusions.

Some win, some lose.

But the good book says that here is a “time to every purpose”. This was not the time to present new demands, and to fix a time-limit for payment, with penalties for delay. You cannot academically say that the figures are right – no doubt they are, but can be overhauled – and that the time has come for the agreed rules to be enforced. Not when there is concern, according to some, that the Union is on the wrong track.

Maybe there is never an absolutely right time across the whole of the European Union to do anything. But it is blindingly clear that the current demand for payment was ill-timed.

The outgoing Commission seems to have lost feel for how to present its decisions. They may have the big stick – for a few days more – but they did not know when to speak softly.

The clear alternative would have been to incorporate any revision into the annual budgetary round, giving the Member states the opportunity to reach a settlement which they could defend to their tax-payers. That is how deals are done, not by going for macho headlines.