It raises two matters that I think are worth dwelling on.

The first involves a number of blood samples that were taken from Russian athletes at these Games, which appeared a surprising success at the time, but have caused the International Olympic Committee (IOC) so many headaches since.

The second involves the "chain of custody" paperwork that is a banal but vital part of an efficient doping control apparatus.

First, the blood samples.

The lawyer, Bochum-based Christof Wieschemann, cites an email that he says was written in September 2016 by Richard R. Young, "as a counsel for Richard McLaren", author of the eponymous report into Russian doping.

This was to the IOC's Richard Budgett.

It has acquired a wider readership than originally intended because it was leaked by the notorious hacker group, Fancy Bears.

The text quoted by Wieschemann includes the following passage:

"Lausanne Laboratory has advised us that they already have a validated method for the detection of anabolic steroids in serum [the clear liquid that can be separated from clotted blood].

"We understand that there are between 53 and 58 Sochi Olympic A and B serum samples from Russian athletes currently in storage at the Lausanne Laboratory.

"We would like to have the Lausanne Laboratory analyse all of those samples for the 'cocktail' of oxandrolone, methenolone and trenbolone, as well as oral turinabol, nandrolone and other anabolic steroids which might be detected in the same steroid screen."

This email was leaked in January 2018.

Before that, and some six days before the hearing that led to Legkov becoming one of the first two athletes to be retrospectively disqualified from Sochi 2014, on October 24, 2017, Wieschemann says he was informed by the IOC in writing that the "blood samples collected on the occasion of the Olympic Games Sochi 2014 were not subject to examination and reanalysis neither within the context of the McLaren Report nor within the additional investigations conducted by the [IOC] Disciplinary Commission.

"We confirm that the IOC limited its investigations to the urine samples."

On February 1, 2018, Legkov was one of the 28 Russian athletes whose Sochi results were reinstated by the Court of Arbitration for Sport (CAS).

CAS stated that in the 28 cases, "the evidence collected was found to be insufficient to establish that an anti-doping rule violation (ADRV) was committed by the athletes concerned".

More than a month after this somewhat happy ending for his gold medal-winning client, in March 2018, Wieschemann says he received confirmation that "different to former statements all blood samples from Russian athletes collected on the occasion of Sochi 2014 were re-tested especially on the three substances of which the 'Duchess Cocktail' allegedly consists - with negative result".

Confused? It gets odder: the fact that the samples had indeed been re-tested had been in the public domain and available to all, including presumably the IOC officials who authored the letter sent to Wieschemann on October 24, 2017, since December 9, 2016.

This is when the IOC published a statement thanking Prof. McLaren and his team for their completed report.

This press release included the sentence: "All 63 blood samples collected from Russian athletes at the Olympic Winter Games Sochi 2014 have already been re-analysed by the IOC in cooperation with Prof. McLaren, and were all negative."

Moving on to the chain of custody paperwork, Wieschemann claims that "almost half of the samples from athletes mentioned on the so-called "Duchess list" arrived at the lab during day time before 4.30pm and were processed within a time period between 45 minutes and 120 minutes".

According to the sample swapping methodology outlined in the McLaren Report, dated July 18, 2016, "the clandestine swapping process would be carried out throughout the night when there were normally no international personnel present.

"By the morning clean urine samples from the night's activity would be waiting in the aliquoting room ready to be analysed by the laboratory's day shift personnel where they would result in negative findings." 

It goes on: "At a convenient moment, usually around midnight when no-one else was in the room, Kurdyatsev would pass the protected athletes A and B samples through the mouse hole in the aliquoting room to the operations room where Dr Rodchenkov and others were waiting."

Wieschemann adds that among the samples that the chain of custody paperwork indicates were processed "during the daytime" were some on which the famous "multiple T-marks" we heard so much about at around the time the IOC Disciplinary Commission was sitting in judgement were observed.

Could the paperwork have been falsified to make it look like samples were processed by early evening when they were not?

Others more cognisant than me of the nitty-gritty of coal-face anti-doping work are better qualified to judge.

Wieschemann (though his English is not perfect) seems in no doubt, writing: "Since the samples and the chain of custody form are part of a sample collection session including samples from all athletes tested on a day at a doping control station in Sochi, not only Russian athletes, the chain of custody forms could not be tampered and were never suspicioned to be tampered."

I put a series of questions about both blood samples and chain of custody to the IOC.

On the latter, it said that it "cannot comment due to pending cases".

On the former, the answer I got back appears admirably candid.

"Blood samples had been re-analysed in autumn 2016 at the request of the team of Prof. McLaren and were negative as publicly announced in December 2016," the IOC confirmed.

"Afterwards there was unfortunately a miscommunication on the side of the IOC which was explained to Mr Wieschemann in 2018 already.

"However, the negative results are not inconsistent with the case as it was also explained to Mr Wieschemann and were not in any way decisive.

"The IOC has clearly shown through its reanalysis programme for the past Olympic Games of Beijing, Vancouver, London and Sochi which led to dozens of positive tests that it uses any possibility to catch doped athletes wherever legally possible."

Why does this ageing sliver from the profoundly damaging Russian doping saga still matter to the extent of me presuming to take you through it in such detail?

Legkov, after all, was cleared on appeal by CAS, although he was still barred from competing in Pyeongchang and has since retired.

Moreover, neither I nor, more importantly Wieschemann, would claim for a moment that various Russian sports bodies and many of its athletes did not have questions to answer over their comportment in recent times.

As Wieschemann writes: "It is not my attitude or approach to challenge the WADA Independent Commission report and the WADA Independent Person report in general or to claim that no anti-doping rule violation occurred in Russia in 2013 and 2014."

The lawyer also acknowledges that "the detection window for steroids in blood is potentially shorter than in urine".

Finally, yes, the IOC re-tests have produced scores of positives.

According to expert Bill Mallon's latest count this month, there are 418 known cases of doping positives and disqualifications at the Olympic Games, including 86 from Beijing 2008 and 121 from London 2012.

But, as a journalist, I hold that truth, even if long delayed, is its own reward. (Stop sniggering at the back there!) 

More importantly in relation to this particular case, recall if you will how that CAS announcement that 28 appeals had been successful (and 11 hadn’t) was received.

Within days, IOC President Thomas Bach declared, with the eyes and ears of the world upon him - and here I quote from Nick Butler's contemporary insidethegames report - that "there is an 'urgent need' to reform the Court of Arbitration for Sport following its 'disappointing and surprising' decision last week to overturn its sanctions against 28 Russian athletes".

On the contrary, it seemed to me last April, having taken the trouble to digest a couple of the key reasoned awards , and I would argue the point even more strongly now, that these cases showed CAS acting decently and honestly and largely as it should.

The now acknowledged "miscommunication" set out above might perhaps, by contrast, suggest that there may be an urgent need to reform the IOC's internal communications channels.