Sooner or later though the host selection process will return to the fore.

So I was interested to see that Professor Bent Flyvbjerg and his team from the Saïd Business School in Oxford have a new paper out. 

The study – Regression to the Tail: Why the Olympics Blow Up – expands on a previous piece of work that had a material impact on the 2024 Olympic and Paralympic hosting race, helping Rome Mayor Virginia Raggi to justify officially withdrawing the city's support from their bid.

That 2016 paper – which I wrote about here – assessed the average cost overrun of successive Olympic projects (156 per cent), and concluded that the Games were "one of the most costly and financially most risky type of mega-project that exists".

The new study is more precise and prescriptive, drawing on statistical analyses of a sophistication I am not qualified to pass judgement on and crystallising its findings into a number of pieces of advice.

Two of these are presented as "heuristics" for cities and countries trying to decide whether to throw their hats into the Olympic ring; the rest as steps to managing the risk inherent in Olympic projects intelligently.

The first "heuristic" in particular strikes me as a fairly sensible fragment of text for future bidders to consider very carefully as one of their last acts before pushing the button on their bid.

It reads: "Can we afford and accept a 20 per cent risk of a three-fold increase or higher in cost in real terms on the multi-billion dollar expenditure for the Olympics?

"If the answer to this question is yes, then proceed and become a host; if the answer is no, walk away."

It is worth emphasising at this point that the analysis only covers sports-related costs, and not those linked to more general transport and hospitality-sector infrastructure that an Olympic project might trigger.

Adherence to such a rule of thumb should prevent the naïve or under-prepared getting themselves saddled with a mega-project they really cannot afford.

But, of course, there are some national and local Governments for whom cost is a secondary concern.

Having scrutinised many bid contests I would say there is also a structural factor that can act as an incentive to keep forecast costings low, increasing the likely magnitude of cost overruns when projects come to be implemented.

This is the requirement for bids to have strong popular support at home to stand any chance of success.

Not invariably, but generally speaking, the bigger the public price-tag, the more difficult bid leaders may find it to secure enthusiastic enough support from the local populace.

Bids which succumb to the temptation to keep costings as low as feasible for the sake of popularity are presumably less than shocked if cost-overruns begin to mount up later on, once the bid has succeeded and the project is in full flow.

Once the host city has been designated, and has guaranteed to meet the event owner's requirements, the immovable (well, almost immovable) delivery deadline becomes more and more of a factor.

Olympic Games are exceptionally complicated, multi-faceted projects.

Even the best-organised will need to work through unexpected snags that could see them falling behind schedule with certain elements.

With an immovable deadline, you need eventually to catch back up, usually entailing extra costs.

Given these specificities, the italicised assertion by Flyvbjerg and team that "larger cost contingencies are needed for the Games" is hard to dispute. 

In terms of actually keeping costs under control, as opposed to being better prepared for when they spin out of control, one partial solution has long seemed to me fairly clear – though how to go about getting it implemented is less so.

I was interested to observe how, during the preparation process for Tokyo 2020, much of the – substantial – pressure brought to bear to keep costs from escalating too high came from the International Olympic Committee (IOC).

This, I think, is part of the legacy of Sochi – costed by Flyvbjerg at a massive $21.9 billion (£16.6 billion/€18.4 billion) – and the fear that future bidders might be put off if spending on that scale were thought to be inevitable.

But that sort of pressure on the IOC might not always be there; and, even with Tokyo, it has not prevented five new sports from being added to the already colossal sports programme.

So it is worth asking how this greater assiduousness regarding cost constraint might be designed into the Olympic process.

Well, as I wrote four years ago: "I think you would find it would make a significant impact if, instead of lumping 100 per cent responsibility on the host city/country for cost overruns, the hosting contract allotted, say, five per cent of the risk to the IOC itself."

I was pleased, then, to read the following in the new Oxford paper:

"The IOC should have skin in the game as regards cost, ie it should hold some of the cost risk that arise[s] from staging the Games.

"The IOC sets the agenda, defines the specs, and has ultimate decision making power over the Games.

"Nevertheless, the IOC holds none of the cost risk involved.

"As a result there is little alignment between incentives to keep costs down and making decisions about cost, which is one reason costs explode at the Games, and will keep exploding.

"For any other type of mega-project such massively misaligned incentives would be unheard of.

"In order to change this state of affairs, we suggest the IOC is made to cover from its own funds minimum 10 per cent of any cost overrun for the Games, to be paid on an annual basis as overruns happen."

Whether you agree with such proposals or not, the new paper, which can be read here, is a stimulating read.

If you are a citizen of Olympicland, or an interested observer, it is well worth an hour of your time.