It was the novelist Jennifer Donnelly who came up with a line about a man on the edge in New York, but that could easily be applied to Scots on the edge at Murrayfield.

A settled side, no injuries, home advantage, a winning record in the Calcutta Cup in the four years that Gregor Townsend and Eddie Jones have coached against each other. Scotland have more Lions in their starting line-up than England, more partnerships with more Tests played together. It points to a home win, but…

For more than 20 years of failure in the Six Nations, these Scotland fans were vaccinated against optimism, but this new variant is breaking through their defences. Scepticism about a bright new dawn is their booster, but positive cases are on the rise none the less. People are worried because hope is breaking through.

It's been amusing to listen to the views of outsiders looking in on Scotland and assessing the collective mindset of the rugby nation.

Once again we heard from Jones that the Scots are expecting glory. The reality is this: if you interviewed every Scottish fan walking through the gate for the Calcutta Cup on Saturday, you'd encounter twisted knots of anticipation and dread. Two decades of failure does that to a fan.

They approach talk of impending joy with suspicion. The Scots have never finished second in the Six Nations, not to mind first. They've been bottom or second bottom on 12 occasions. They have four wooden spoons, three of them with five defeats out of five.

The uppity, expectant Scots of Jones' imagination? No. A rugby people who are anxious about falling down the well of optimism yet again? Yes, with bells on. Frankly, and to paraphrase Muhammad Ali, if a Scottish supporter thought of a Six Nations title in their dreams, they'd feel the need to wake up and apologise.

But here we are. Last season, Scotland had one of the best attacks and one of the best defences. They scored more tries than they had ever scored in the Six Nations and conceded a near-record low number of points.

They had the leading try-scorer - Duhan van der Merwe - and the official player of the tournament, Hamish Watson. Chris Harris was on the best defensive centres. The back-row was an aggressive amalgam of carriers and spoilers. Then there was Stuart Hogg and Finn Russell. They're all back in harness. For once, the treatment table lies empty.

They won three, could have won a fourth had Zander Fagerson not got himself sent off in a one-point game against Wales and might have sneaked a fifth had their line-out not collapsed to the tune of two successes from nine throws in a three-point game against Ireland.

In France, they had Hogg yellow-carded and Russell red-carded, their two creative totems. And still they triumphed, in the last play. Since then, they've beaten Australia and Japan. South Africa's power proved too much for them.

Over the last two seasons, they have won as many Six Nations matches as England and Ireland and have one more win than Wales. Over the span of those two years they've conceded fewer tries and fewer points than anybody else. This is a seismic shift compared to the sieve that Scotland used to be.

Jones was entitled to reflect some of this in his pre-match mind games, but you'd have to imagine that the psychology of Townsend's team is immune to that stuff. Jones tried it on last year and Scotland won at Twickenham, he noised them up again before the 2019 game and Jones' team blew a 31-0 lead.

He delved into the same old playbook before the 2018 game when attempting to mock Townsend's gameplan as side-to-side rugby that got everybody at Murrayfield hugely excited. That was the year that Russell threw that pass that led to that try, an end-to-end epic done at speed. Eddie had to eat his words in the aftermath.

"They're expected to win," Jones said of Scotland. "That expectation of winning is a different pressure to handle and I'm not sure how they handle that." It's Eddie shtick. Having lost two out of four, he really should come up with a new routine. This one has been on the road a long time and it needs a rest.

Will Jonny Gray's trousers catch fire just because Eddie is reheating old lines? Hardly. Of course, Jones had an ulterior motive when he spoke about Scotland being "red-hot favourites" who had to "carry that burden." Had he shrieked and cried 'Squirrel!' the deflection tactic wouldn't have been any more obvious.

Of the England team that beat South Africa in the autumn, Manu Tuilagi, Jonny May, Jonny Hill, Courtney Lawes and Sam Underhill are all out. So too is Owen Farrell. The power of the Vunipolas is missing. Joe Launchbury is not there. Anthony Watson's class is absent.

Two of his side - Elliot Daly and Nick Isiekwe - weren't in his original group of 30. Daly and Henry Slade are the 21st centre combination of the Jones era. Given the vast resources he has available to him, Jones still fields a team of rich promise. It's a team built to play, to take Scotland on at their own high-paced game. This is not a wrecking ball England, it's a beast of a different kind.

Two back rows with ferocious disruptive capabilities and two fly-halves - Russell and Marcus Smith - who are glorious footballers and inherent risk-takers. It all depends on whose pack moves forward and which of the two of them gets an extra second to wreak their havoc.

Had Townsend wanted to retaliate in the verbals then he had some heavy ammunition at his disposal. England finished fifth in last season's tournament, an unimaginable failure for such a powerful rugby nation were it not for the fact that it was the second time in four years that they finished one from the bottom under the Australian.

Jones said that Scotland are probably "two years ahead of us in terms of their development". To that, Townsend might have asked what Jones has been doing with his team all this time. There's huge pressure on both coaches on Saturday, but the more Jones attempted to focus on Scotland, the more he sounded like a man who was worried about what was happening with England.

Two years ago, his team won in a Murrayfield monsoon, the type of conditions that brought to mind a story told by Paul 'The Judge' Rendall about a bitingly cold Calcutta Cup day in Edinburgh. "All I wanted to do at half-time was go and buy two cartons of chips and stick my feet in them."

Different days, those. Different days, these, for Scotland. But how different? The day that hope lived, or the day that hope died?