Back in 1999, Wales wrecked England's grand slam and handed Scotland the title, the day after the Scots had torn their hosts to shreds in Paris. That weekend began a strange sequence in which England were denied grand slams in each of three successive seasons by each of the Celtic teams in turn. Scotland, without a win to that poihnt, had triumphed at Murrayfield in 2000, surprising the favourites even more, before Ireland won the last of the "foot and mouth" Tests in the autumn of 2001.
Since then, only the World Cup-winning team of 2003 has won a grand slam for England in an era in which their player numbers and overall resources mean they should have won many more.
Ten years on, under Stuart Lancaster's pragmatic coaching, they are within touching distance of another, since victory over a Sergio Parisse-less Italy (barring a successful appeal against his 30-day ban for abusing an official in French domestic rugby) is reasonably seen as a formality.
This has, though, already been a very strange RBS 6 Nations, with five different teams winning the first five matches, the only team not among them being pre-tournament favourites France who, three rounds in, have still to win a match.
How have we got to this point and what might happen next? As we seek to reflect and project, the key questions and answers are as follows.
What needs to happen to set up a potential repeat of 1999?
The same two fixtures occur on the final weekend, but this time the schedule seems to favour England and not just because they are first in action this time.
If it is to be accepted that they will not, at Twickenham, suffer a first defeat to Italy, the only real chance of them being denied a grand slam will be if Wales beat them in the Millennium on the final weekend.
Between now and then, Wales must visit Murrayfield and should they lose that match their incentive to beat England would seem reduced since they could no longer defend the title they won last year.
Yet, the idea that Wales would ever lack motivation against England is as ridiculous as it would have been to suggest that Andy Nicol and his men would not give everything they had against the Auld Enemy in 2000. In some ways a Scotland win at Murrayfield next week could even free up Wales slightly since they currently trail England by 17 on points differential so, if they do still have a title chance, they could get caught between two stools on the last weekend if left with a target beyond simply winning the match.
In may ways, then, a gritty Italian performance against England allied to a rousing home win at Murrayfield, could just give Scotland a realistic chance of closing the points differential gap on the final weekend.
How on earth have we got here?
So far England have been by far the most impressive team while Scotland have recovered from being comprehensively beaten by them on the opening day to find a way somehow of winning two Test matches back to back in startlingly different ways.
After that Twickenham defeat, Scotland were staring directly at the prospect of suffering the humiliation of successive championship "whitewashes" had they lost to a rampant Italian side that had already shocked France.
Instead, in a performance that made a mockery of many rugby orthodoxies as well as their own recent history of being the worst finishers among international rugby's elite, their counter-attacking brilliance sent the Italians into shocked disarray.
Two weeks later and Scotland claimed a second successive championship victory for the first time in a dozen years, with a performance comparable only in the defensive resolve shown and the taking of what meagre chances came their way.
There was nothing remotely stylish about the reversion to what beat England at Murrayfield in 2006 and 2008 and Australia in 2009 and last year, as they refused to yield in spite of all the evidence for much of the afternoon that even a sub-strength Ireland were far superior.
Rather than backs rattling in tries, the only points came from Greig Laidlaw's right boot, just as they had against Australia in Newcastle last summer and, as in such a high percentage of Scotland's wins in the past six or seven years, they won while losing the try count.
Yet Scotland have faced title eliminators in their last two matches and have come through both.
That they have finally won back-to-back matches and have done so in strikingly differing fashion offers encouragement, then, but is it enough?
WHAT NEEDS TO HAPPEN IF SCOTLAND ARE TO HAVE A TITLE CHANCE?
There was something highly amusing about the way some journalists were upset on Sunday by reports that Dean Ryan, Scotland's forwards coach, had criticised the media for becoming over-excited about the team's efforts so far. Those whose noses were out of joint really need to remember that almost everything coaches say ahead of matches is intended to be read, for whatever reason, by their own men or the opposition.
For years the Murrayfield moan has been that some elements of the Scottish media are not supportive enough. The truth is that there is always plenty of knee-jerk cheerleading and poison-penmanship depending on results, but no serious analyst had said of Scotland's win over Italy that it represented anything other than much-needed encouragement. However, if we thought the outcome there was remarkable given the way the statistics, other than the scoreline, stacked up in Italy's favour, it was nothing to what happened on Sunday.
Week on week, since Twickenham, it has become ever more clear that Ryan is getting through to the forwards that they must be more brutal yet simultaneously more disciplined if they are to win the gain-line battle, and some progress is being made. Instead of coming into international camp and, as seems to have happened under Andy Robinson and Gregor Townsend, being heavily coached, there seems to be a renewed acceptance that Test rugby is about identifying those the management consider the best available, then finding the best way of utilising what strengths they have on the day.
Realistically the arithmetic says that Scotland have no title chance this time around but, if they are to be the closest challengers to England, that process has to move on once more next weekend and again the weekend after. To beat Wales, they will need to get somewhere close to parity in terms of possession in particular; to beat a France team that showed signs of remembering itself against England on Saturday, even more so.
For these remaining matches they will need their free-flowing backs rattling in tries as against Italy and Greig Laidlaw belting over all his penalties as against Ireland.
However, for both to be allowed to happen on the same day will require far better decision-making and execution of skills in the combat zones than Scotland have exhibited thus far. And they know it.