Playing or competing on your home patch has, traditionally, conferred extra powers which are explicable – but never wholly so.

By way of illustration of the complexity of this topic, a research paper into home advantage in the Summer Paralympic Games, published in 2017 by Darryl Wilson and Girish Ramchandani for the Sheffield Hallam University Research Centre, concluded: "In summary, there is clear evidence of a home advantage effect in the Summer Paralympic Games at country level and for certain sports. 

"Although we discuss some possible reasons for these findings, the causes of home advantage in the competition remain unclear."

The run-up to the London 2012 Games provided ideal circumstances for UK Sport to address the perceived phenomenon of "home advantage" by analysing past Olympic results. So they did.

Anecdotally, it is a truth universally acknowledged that home competitors derive inspiration and motivation during international events.

That said, Michael Johnson, the former world 200 metres and 400m record holder, has begged to differ. 

The quietly spoken American, never averse to voicing opinions against the flow, announced that performing at home simply increases the pressure on performers to live-up to escalating expectation.

Just think how well he might have done in 1996 – when he won Olympic 200m and 400m gold, the former in a world record time – had the Games not been held in Atlanta, Georgia.

Whatever the logic of Johnson's position, the universal truth has been attested to time and again by home athletes – before, during and after the London 2012 Games.

The UK Sport officials found, and acknowledged, that there was indeed a recorded, quantifiable example of "home advantage" at different Olympics over the years – and that home advantage could be seen to operate most clearly in the area where sports were judged.

Down the years, academic studies attempting to document what happens when a home team or athlete appears to thrive have looked at four main factors to do with the crowd, learning or familiarity, travel and rules. 

It has also been surmised, not too adventurously, that the bigger the crowd, the bigger the effect on the match official. 

As is often the case in areas such as these, science merely seems to confirm what everyone thinks they knew already.

Sport already acknowledges these factors with well-worn phrases – the "home-town decision" and, where referees and judges are concerned, the "homer". 

Statistical surveys of Summer and Winter Games have identified a particularly marked advantage for home nations where medals are awarded by judges. 

And crowd noise is thought to be a telling factor in aligning judges with home individuals or teams.

Instances such as we have just witnessed this weekend, with the Bundesliga re-starting play after coronavirus lockdown, but behind closed doors, offer a perfect opportunity to re-assess the part home advantage, and in particular home crowd advantage, play in affecting results.

In his column in The Guardian today, Sean Ingle cites Opta statistics from the Bundesliga matches played over the weekend which show that the preponderance of fouls given against away teams, and of yellow cards handed out to them, ceased to apply in the matches played without spectators.

In the 224 Bundesliga games this season before the lockdown, referees awarded 151 more fouls against away teams and showed them 62 more yellow cards. In the closed-doors matches, however, slightly more fouls and yellow cards were awarded against the home teams on average.

Previous academic studies into football have identified a tendency for referees to favour home teams when adding on stoppage time beyond the regulation 90 minutes. 

Again, this is research that chimes in with popular perception, as the celebrated "Fergie Time" – apparent extra helpings of time given to Manchester United when they were under the charge of the indomitable Sir Alex Ferguson – attests.

On the eve of the Bundesliga matches theconversation.com published the work of three economics experts offering more statistical evidence to back the idea that referees tend to favour home teams when it comes to adding on extra time or penalising opponents – that is, while being under the vociferous surveillance of many thousands of hugely biased home fans.

Indeed, they found that the level of the effect is governed by the size of the crowd involved.

The three academics involved in this work have studied the effect of games played behind closed doors since the Second World War, a process involving 191 matches, most of them since 2002.

"We have found that the considerable home advantage in football is on average almost entirely wiped out in closed doors matches," the article says.

"Historically, home teams win 46 per cent of the time in matches with fans, but only 36 per cent of the time when there are no fans. 

"The away team wins 26 per cent of the time with fans, and 34 per cent without fans."

The article goes on to conclude, most interestingly: "The evidence also suggests that the current wrangling among the English Premier League's clubs about playing their remaining matches at neutral venues, is based on a mistaken notion that home advantage wouldn't disappear if they play some of their remaining matches in their own empty stadiums."

So it's not, after all, about the fortress, but those lining the walls to defend it…