Tom Griffin (London, The Green Ribbon): Ian Paisley Jr became the first Minister to resign from Northern Ireland's Stormont administration this week. His departure is widely seen as a signal that his father's retirement as First Minister is only months away.
On one level this is a significant demonstration that democratic accountability is possible within Stormont's cross-community coalition system. Yet it also reflects a new threat to the stability of the Executive.
Paisley Jr's resignation came about as a result of series of freedom of information releases highlighting his relationship with businessman Seymour Sweeney. Perhaps the most important document was uncovered by MEP Jim Allister, who left the DUP last year because of his opposition to entering government with Sinn Féin.
This showed that in the run-up to the 2006 St Andrews agreement, Paisley Jr lobbied Tony Blair in favour of a number developments linked to Sweeney. In Allister's view, this was "wasting valuable leverage on securing concessions from the PM no less, not on matters of importance to Unionists, but on issues of mere commercial or constituency import."
The revelations played into what has become universally known as the 'Chuckle Brothers' image - the perception, unpopular among unionists, that Paisley Sr has developed a surprisingly cosy relationship with Deputy First Minister Martin McGuinness.
Internal DUP rumblings grew louder after last week's Dromore by-election, an otherwise minor council poll that saw Allister's Traditional Unionist Voice (TUV) take enough votes to hand a previously safe DUP seat to the Ulster Unionists.
Paisley Jr decided to go before he was pushed by a group of senior party figures who met in Portugal at the weekend. His father dismissed speculation about his own position during a visit to Edinburgh on Wednesday.
However, according to the usually well-informed Irish Times, DUP MPs are pressing for a hand-over of power by September:
In an echo of the original - though in the end disputed - Tony Blair/Gordon Brown "Granita deal" over the Labour leadership, the growing expectation seems to be that Nigel Dodds MP will back a [Peter] Robinson succession on the understanding that Mr Robinson will in turn support Mr Dodds to become only the third leader in the DUP's history.
As a key architect of the DUP's current strategy, Robinson is a known quantity to the other players in the North, but his approach is likely to be shaped by the challenge from the TUV.
Brian Feeney of the Irish News suggests that will mean a rough period ahead at Stormont:
Straight faces will be the least of it. It looks unlikely that policing and justice will be devolved before next year's European election, for which the DUP have yet to nominate a candidate. Don't even mention the 11-plus.
The DUP MPs who face the voters in 2010 and are the men who put the kibosh on Ian Og will keep SF at arm's length until they safely retain their seats.
The TUV's success in Dromore may well turn out to be a flash in the pan. Nevertheless, the result is likely to slow the pace of devolution in Northern Ireland, at precisely the moment when it is accelerating elsewhere in the UK.
