The beauty of the sport of rugby is that with every new season you can detect subtle changes in the comparative importance of positions.
In terms of fundamentals, things don't vary too much. But every so often, and for a number of reasons, a shift happens at a tectonic level and the playing field is altered for good.
Such a shift has happened over the past few seasons. Glacial at first, the progress has greatly accelerated over the past 12 months, kind of like an Auckland house price, or plans to turn New Zealand into an oil well, and the evidence is now beyond contradiction. In short - or should that be tall? - lock forwards have asserted themselves as the genuine all-round power players of the game, and a team's performance can now be directly correlated to their ability to gain dominance on the field.
Such a grandiose statement deserves some qualification, and so I shall offer the following: the rise and rise of the power lock does not dismiss the greats of past eras - after all, there remains just one Sir Colin Meads - and it does not detract from the importance of other positions in terms of netting the desired result. A team's spine still effectively controls the outcome, but that spine - stretched to breaking point offensively and mercilessly compressed on defence - has in the modern lock a substantially strengthened core.
Long gone are the days when any old tall man who could win the occasional lineout would do. There was a time - somewhere between the death of Kurt Cobain and the birth of Lydia Ko - when height almost superseded any other requirement for a lock, leading us in rather gangly fashion into an age of large men whose nerve fibres seemed to stretch only so far as the elbows and knees, effectively leaving them with four independent half appendages which, quite frankly, were incapable of co-ordinated athletic endeavour.
The word "core" is as good a word as any to illustrate the changing nature of a lock's job. The lock's core responsibilities, while still grounded in the inimical pursuits of hitting rucks and jumping in lineouts, not to mention pushing in scrums, have now been widely broadened in scope to include topping tackle counts, winning regular turnover ball and operating as a strike runner.
There is a chicken-and-egg quandary in all of this. Has the role, and therefore the selection criteria, changed because of the athletes now filling the jerseys? Or are the athletes being selected because of the ongoing evolution of attack strategies? That is a tough one to answer. To use a Springboks-All Blacks example the likes of Victor Matfield and Bakkies Botha, Ali Williams and Brad Thorn certainly punched out a template for the position, but all of them operated at a time when rugby's systems were changing to reflect a truly 15-man game. So the "which came first?" question remains unanswerable.
That is not the case today. The likes of South Africa's Eben Etzebeth, Scotland's Richie Gray, England's Courtney Lawes and New Zealand's Sam Whitelock and Brodie Retallick all represent the new breed: uncompromising power athletes with skill sets to match outsized physiques.
Judging a lock's value in a game of rugby has always been a tough task because the position, for so long, lacked any real, er, glamour.
The try-scorers and the loose forwards and the first five-eighths never go unnoticed, but the locks, well, they may be close to seven feet tall but when half of their body is buried in a pile for most of the match, height's not enough to get them the starring role.
And let's face facts: it is easy to compliment the quality of the eye fillet while forgetting about the mashed potato.
Make no mistake, though, when all is said and done and this All Blacks season finally concludes with what most believe will be a comfortable victory against the Irish (I have tried to find a way to offer some hope to the Irish fans, but with an injury list as long as Joe Schmidt's, my pint of Guinness is unfortunately half empty) praise should be lavished on the likes of Whitelock and Retallick, who continue to astound with the size of their respective engines.
The importance of the locks to a team's chances of winning is illustrated in full by the workloads of these two men in a modern game during which they are expected to scrum longer, jump higher, tackle harder, run further, and clean out more often. The changes in the way locks play the game may have developed in subtle fashion, but the impact of these two men during what has been a remarkable All Blacks season has been quite the opposite.