The idea of the grand coalition - and the FF/FG love that dare not speak its name
The one thing that Enda Kenny and Micheál Martin are absolutely in agreement about is their common refusal to contemplate a grand coalition of Fine Gael and Fianna Fáil before polling day.
They justify their ambiguity and evasion using solid arguments based on short-term tactics.
Fianna Fáil is in a bind: if it makes any show of intimacy towards Fine Gael, this would give ground to Sinn Féin, which would pounce on any anti-Government votes that might have gone the way of Fianna Fáil. The question for these voters would be: "Why vote for Fianna Fáil, if it is merely going to prop up Fine Gael?"
Meanwhile, for Fine Gael to play footsie with Fianna Fáil would be tantamount to the tacit release of the 500,000 or so votes they were loaned in 2011. Disenchanted Fianna Fáilers might begin to think: "It's okay to return to the fold, we're heading in the same direction anyway."
Therefore, Fine Gael must paint Fianna Fáil as the devil incarnate, reminding the voters of how it crashed the economy.
There are also valid long-term reasons for opposing any rapprochement between the two historic foes.
For decades, it suited both parties to alternate in office. The unpopularity of one Civil War party facilitated the other party's return to power. In such a way, the continuity of centrist, nationwide 'catch-all' Irish government was assured.
This circumvented the need for ideological somersaults and prevented the emergence of a strictly class-based politics. Policy cornerstones - such as attracting foreign direct investment through low tax on corporation profits and the absence of overt wealth taxes - survive intact despite regime change.
The arrangement also facilitated a cosy consensus within which political careers flourished. Critics decry this as Tweedledum versus Tweedledee. It has enabled permutation without revolution.
However, General Election 2016 could smash this traditional pattern to smithereens. Several years of austerity now threaten to push the combined Fine Gael/Fianna Fáil market share below the threshold that would let either party govern without the other.
My guestimate for the configuration of the 32nd Dáil (based on national opinion polls and the totals of 40 individual constituency predictions) is: Fine Gael, 55 seats; Fianna Fáil, 35 seats; Sinn Féin, 25 seats; Labour 10 seats; Others, 30 seats.
Ergo, the outgoing team won't have the numbers for re-election.
Four coalition options are possible: Fine Gael and Labour combined with Independents or small parties; Fine Gael plus Fianna Fáil; Fine Gael plus Sinn Féin; Fianna Fáil with Sinn Féin, Labour and Independents.
The first and last options wouldn't last beyond the next budget, triggering another election in November. This is exactly what happened in late 1981, when Jim Kemmy and other Independent TDs voted against VAT on children's clothes and footwear.
A temporary minority government could be formed by Fine Gael. It's inevitable a 'Tallaght Strategy' would put intolerable pressures on those propping up the lame-duck administration, while incumbents would be eyeing the first opportunity to bolt to the country to secure a majority mandate.
It's a recipe for economic uncertainty, with potential reputational damage for Ireland Inc as an investment location. The roof wouldn't cave in, but in the context of volatile global markets, GDP growth could be vulnerable.
Already, disquiet is emanating from business leaders about the irresponsible tenor of election campaign promises. Ibec is appalled at give-away pledges to cut income taxes, increase public sector numbers and welfare rates and ramp up spending in the Health, Education and Justice departments.
Such fears are tepid in comparison to the blind panic in some quarters at the prospects of either Sinn Féin or socialists having their hands on the levers of power. One also senses real terror at the possibility of any change in the tax treatment of executive salaries. There's fears that an anti-business sentiment could prompt a flight of capital. Worries that market 'confidence' would be scuppered have also been voiced.
My guess is that post-election, pressure will build from the forces of capitalism to prevent any left-wing thinking getting a hold inside Government Buildings. Scenarios of a perfect storm involving a Brexit and a Chinese collapse will concentrate hearts and minds.
This will put massive pressure on Messrs Kenny and Martin to enter a coalition. After all, both of their parties loyally implemented the Troika bailout programme, share a commitment to adhere to EU fiscal rules and are pro-enterprise. They also share a common approach to important macro-economic and fiscal policy.
Both men are in the autumn of their political careers. Kenny has been party leader since 2002, and is Father of the House. Martin was a cabinet minister for 14 years from 1997. If the next Dáil lasts the full term, this may be their last electoral contest. An opportunity to reconcile a historic conflict beckons.
However, the obstacles for Martin are probably steeper. Generations of his party's followers dedicated their lives to opposing Fine Gael. There would be obvious risks in being the leader of the smaller party in government - as the unhappy experience of former junior coalition casualties such as the PDs, Greens and now Labour, suggests.
Gains of 15 seats could make Fianna Fáil cumainn members lean towards the idea of growing the party in opposition, in preference to the poisonous embrace of Fine Gael. Under Fianna Fáil rules, a special ard fheis is required to endorse government participation - a prospect not likely to appeal to tribal die-hards. Having escaped obliteration in 2011, entrapment by Fine Gael probably doesn't hold too much appeal.
So Martin is between a rock and a hard place. There's no risk-free route. If out of government, Fianna Fáil could be vulnerable to a repeat snap election - for which he'd be blamed because of his refusal to participate in government.
And who's to say that another five years of Fine Gael in office (albeit with Fianna Fáil) wouldn't make the Blueshirts insufferably arrogant - and therefore even less popular than Fianna Fáil.
Fianna Fáil is accustomed to power, and cute enough to build voter appeal. Meanwhile, the alternative possibility - a future Fianna Fáil-Sinn Féin government - scares de Valera's inheritors.
Giving both leaders the maximum wriggle room after the election seems to me to be in the national interest. Holding them hostage to rigid positions makes little sense.
Let's facilitate future possibilities that may avoid a second election, paralysis in government and economic risk.
But the grand coalition option may be unthinkable to each party's die-hard loyalists - so perhaps the idea of people putting country before party is crazy, idealistic nonsense.