Fine Gael-Sinn Féin is not totally 'unthinkable' - if we go by recent history
Are Sinn Féin really the 'political untouchables' Enda Kenny and Fine Gael would have us believe?
Well, let's look back on 2007 when the Green Party joined government with Bertie Ahern's Fianna Fáil. Fine Gael and Labour were livid, as they had counted the Greens in their would-be 'Anybody But Fianna Fáil' (ABFF) line-up.
Facing another opposition stint, Fine Gael and Labour unearthed the Greens' worst anti-Fianna Fáil pre-election comments. In spiky Dáil exchanges on June 14, 2007, Green Party leader, Trevor Sargent, suggested Fine Gael should have approached Sinn Féin and tried to put together a coalition.
Fuller details of what he was alluding to emerged two years later, with bad-tempered exchanges between Fine Gael and the Green Party during the 2009 local elections. Both Trevor Sargent and John Gormley, his successor as Green leader, told stories of approaches from Fine Gael after the 2007 general election.
The idea was that the Green Party should 'sound out' Sinn Féin about coalition. If Sinn Féin's four TDs came on board, then the would-be 'ABFF coalition' would have 84 TDs - just about a majority in the 166-seat Dáil.
The Greens said they had told Fine Gael to do their own 'sounding out'.
Sargent added a note of farce with a 'Ballroom of Romance' analogy about "ask your sister if she'll go with me".
Two of the Fine Gael principals cited - Phil Hogan and Enda Kenny - totally denied that any such thing happened. Fine Gael argued that it was just "desperation stakes" from the Greens facing local election wipe-out.
They were right about the election outcome, as the Greens went from 17 to just three council seats. But the reason the issue arose at all at that stage was that, just days earlier, Fine Gael strategist, Frank Flannery, had raised it.
Mr Flannery wrote a Sunday newspaper article in which he said they could "do business" with Sinn Féin. Party leader Enda Kenny instantly disowned the comments and announced he was demoting Flannery.
On the other side of the equation, Sinn Féin has always gloried in insisting that Fine Gael were really beyond the beyonds when it came to considering government partners.
But in Belfast they have shared government for the past eight years with the party Ian Paisley created.
Meanwhile, in various councils around the country, councillors from both parties have been quietly collaborating for a long time now.