Governing bodies the world over can be certain of one thing only – they will be the subject of endless criticism. No half-serious journalist will write for long without taking the authorities to task over something, and journalists are the sensible ones. The public do the same but – how to put this – with extra feeling. All the time.

World Rugby is as assailed as any governing body. Its own players are taking it to court, after all, with the not insignificant claim World Rugby ruined their lives. That lawsuit may or may not be sitting at the top of an in-tray that creaks under the weight of grievances, most of them irreconcilable.

This column has had its fair share of pops at our beleaguered masters, but it would be uncharitable not to pause for a moment to acknowledge the truth that World Rugby’s remit, to promote and safeguard the interests of rugby union, must be about the most thankless, nay impossible, remit in all of sport. Well, apart from that of all the other governing bodies of collision sports.

Last week, World Rugby staged a series of online seminars, the third of which was poignantly titled Safety vs Spectacle. Ross Tucker, World Rugby’s science and research consultant, kicked off by saying with beautiful understatement: “I think we have reached a point where it is beneficial to admit that sometimes there are tensions [between safety and spectacle].”

Sometimes? Tensions? World Rugby might not be able to come out and say this, but we can. Those two directives – to improve player welfare and make the game more entertaining – are in direct opposition to each other. Always.

Any collision sport is at its safest during its slow patches and at its most dangerous in the exciting, high-speed bits. The greater the accent on the latter, the greater the toll on the players – and, most importantly, given the aforementioned lawsuit, their brains. Speed the game up, increase the collisions and their intensity. That is less the tension, more the conflict at the heart of all collision sports.

After yet another extraordinary weekend of European rugby, we are presented with a sport that continues to amaze us with the frequency of its breathtaking matches. Even the one-sided contests were spectacular to behold. But they made you wince as well. That crunch, as much as the brilliance, is fundamental to the awe-inspired.

In an earlier seminar on the instrumented mouthguards (iMGs) World Rugby is starting to deploy across the elite game, a study in Boston last year was alluded to, that provided the most detailed and compelling evidence yet of something neuroscience has been saying for years. The risk of chronic traumatic encephalopathy (CTE), the disease at the heart of the players’ lawsuit against rugby’s governing bodies, is most strongly correlated not to one-off concussions but to the cumulative toll of multiple head impacts over many years.

This has major connotations for all collision sports. And rugby union is, and always has been, one of those. The nostalgists who claim it used to be a contact sport really mean it used to be a collision sport that had not yet powered itself up. Science, technology and professionalism, probably in that order, have seen to that now. Everything is vastly improved – and thus vastly less safe.

The Boston study used data from iMGs. World Rugby is now diving deeply into the same technology. Data was presented from the Six Nations just played. Each match featured roughly 1,000 “head acceleration events”, which means the abnormal injection of energy into the skull, as measured at the teeth. Most of these, of course, are harmless in isolation, but it is the cumulative toll that is fast becoming the key area for investigation.

It is difficult to know what to do about this. In a later discussion during the Safety vs Spectacle seminar, Ugo Monye argued that the game had become scared of itself and, to much vigorous and rightful nodding of heads, that it was at heart a physical sport that people play and watch precisely because of the collision element.

This cannot be denied. Just coaching children of certain ages is enough to make vivid the instinct in so many to want to collide with each other. Long before they are allowed to, children of various sizes will entreat their coaches: “Can we do some tackling now, pleeeeaaaase!” And even for those who do not fancy it there is the equally addictive prospect of successfully evading the same. But we do need those collisions for rugby to remain, as the saying goes, rugby.

Which means it becomes a question of quantity. Even that raises impossible questions. How much is too much? How much is enough? Of all the myriad campaigns to save the game we love, not one has come up with a credible solution to any of this. One thousand rattlings of the brain is quite a lot to undo.

Reducing full-contact training is an easy win, but very few teams overdo that these days (the science of preparation has seen to that). The jackal is on borrowed time – and banning hands after the tackle may shift the dial a little. Other than that, the most obvious solution is to play fewer matches. But how many fewer?

Is there a tipping point beyond which rugby becomes dangerous? Or does reducing match exposure by, say, 25% merely reduce cases of CTE in later life by 25%? And how can we know the effects of any changes without having to wait decades?

Even as new heights of brilliance are being attained, a pall of uneasiness hangs over rugby, as with a prisoner awaiting sentence. Who would be a governing body?

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