Think for a moment of the 'public private partnerships that have been the mainstay of the Irish rugby team in the 21st century.
O'Driscoll and D'Arcy. Stringer and O'Gara. O'Connell and O'Kelly (or O'Callaghan, for that matter). These three partnerships have been subsumed into the public consciousness to the degree that, in the same way as one wouldn't refer to Hardy and Laurel, the order in which they are described seems pre-ordained. Horan and Hayes aren't a million miles off that.
Other partnerships are more fluid, but are establishing themselves. Leamy, Easterby (or Best) and Wallace don't exactly trip off the tongue at the moment, but are on their way to making it so. That said, the backrow is so competitive an area traditionally, that you arguably have to go back to Matthews and Carr for the last truly recognisable flanker partnership.
That these partnerships are so public doesn't invalidate their essentially private nature. The success of these pairings is based on individual skills that mean that the individuals bring a lot to the party. But the true value to be derived from them goes beyond the sum of their individual parts (see how I cleverly avoided the dreadful 'synergy' word!). (see how I cleverly made it the only word in bold in the paragraph? Ed.)
The real beauty of these partnerships lies in the levels of understanding of each other's play. This might be simply down to your correspondent being a former back, but I believe that in the case of the above three cited partnerships the two backline ones are the most important in terms of this understanding.
In this regard, no partnership in the world can be more comfortable with each other's game than Stringer and O'Gara. Famously together since schooldays, the number of passes thrown by Stringer to O'Gara must number in the tens of thousands. At this stage, Stringer must know without signal, the side that his outhalf wants to go, when he wants it flat, when deep. In recent times, only Laidlaw and Rutherford, Farr-Jones and Lynagh, and Gregan and Larkham begin to compare in terms of comfort levels with each other.
If it's important at half-back, then it is equally so at centre, as the two must work together so closely in terms of both attack and defence. Timing is as important to international centres as it is to stand-up comedians. In particular, in defence it is critical. Knowing the nanosecond when it is safe to drift off because your inside man has you covered means an intimate knowledge of your partner's capabilities and thought processes. Knowing just how long to hold the ball up to enable your partner to time his run against the grain is the offensive equivalent. Playing against the top international teams, any hesitation is fatal.
Looking at Leinster playing against Llanelli last weekend, it was quite apparent from their defensive uncertainty that they hadn't been playing together regularly. Luke Fitzgerald injured himself needlessly when he came in to make a tackle he didn't have to, and in so doing enabled the Scarlets to score handily. Had he played more regularly with Kieran Lewis, he would have known Lewis had the second last man covered, wouldn't have suffered a head injury and consequently would surely have not allowed Regan King to escape his clutches minutes later.
O'Connell and O'Kelly may have given way to O'Connell and O'Callaghan in the second row, but the intimate knowledge level has actually gone up as a result. These two epitomise the degree of understanding that is present throughout the Munster, and by extension, the Irish pack.
As much as the individual skills brought to bear on the equation, it is this comfort with each other that enables Ireland to trade punches with the very top nations. It is manifest in the way that there is no semblance of panic when the early portion of the game goes against Ireland. At this stage, they know that they are not going to be swamped by anybody.
Contrast this with the fear evident in the faces of Irish teams of the nineties as they regrouped under the posts after France had scored their first try. Everybody knew that there was a fair chance that they could be seriously exposed.
When Eddie O'Sullivan was making his pitch for the Irish job, he majored on making the team more consistent. He has achieved this in some style - in part because, through consistency of selection, he has been handsomely rewarded by some outstanding 'public private partnerships'.
Expect this RBS Six Nations to see Ireland reap the dividends of these partnerships.