There were too many times when the power and the composure of the England renaissance – and the assumption that the Triple Crown, Grand Slam and full-blown redemption await formal collection at the Millennium Stadium next Saturday – not only flickered but seemed to have burnt away.
A team that has been growing so impressively for a year or so was scaled down for a variety of reasons but mostly they seemed to be operating in the shadow of great players.
One of them was the restored Sam Warburton of Wales, who at Murrayfield 24 hours earlier had not only looked as though he had picked up his bed to walk but a rather wider array of household furniture with which to batter England.
The menace of Warburton and Wales' iron-clad defence might just have been a fatal distraction as Italy's brilliant second half brought white-knuckled tension to Twickenham. There was also that other image of the extraordinary commitment required of the great champion players so vivid in Dublin when Brian O'Driscoll, swathed in bandages, returned to the field to help resist a France who had apparently remembered how you play seriously competitive rugby.
Could this new England strike such levels of authority and character so close to the climax of their remarkable domination of the Six Nations tournament and some more than fleeting evidence their ransacking of world champions New Zealand last autumn might just be an earnest promise of things to come?
No, they could never make that a serious possibility, a fact they conceded with the most eloquent body language of relief when Irish referee George Clancy – who had earlier grievously wounded the Italians when he wrongly called a knock-on when they bore down on the England line – signalled an English victory by just seven points.
England coach Stuart Lancaster can only hope that he is able in the next few days to recreate the sense of a team moving forward with quite relentless application. Here, they were anything but that. In the first half they ran guilelessly at an apparently vulnerable Italy but, with Toby Flood slotting over the penalties achieved by England's forward dominance, there was a case to say that this might be no more than a timely reminder that a much sharper and more fluent game had to be taken to Cardiff.
This, though, was before another great player intruded into the consciousness of the putative Six Nations champions.
Inspired by the ageless brilliance of Sergio Parisse, Italy came hauntingly close to delivering something far more serious than a bracing scare. They came very close to destroying England's vision of a season filled with great promise for the future and, at the very least, a significant impact on the 2015 World Cup. They pushed England to the point of destruction and their own first victory in a place which had previously promised only death by the sustained infliction of superior power.
Parisse delivered a thrilling lesson in imaginative leadership. If the English pack opened with some impressive power, the Italian No 8 never yielded for a moment the idea that he might work some miraculous level of resistance and, when his back division began to deliver moments of penetration and flair quite beyond their English counterparts in the second, the odds against such a possibility shortened quite dramatically.
Full-back Andrea Masi ran with both power and invention, wing Giovanbattista Vendetti stretched the seams of English defence each time he possessed the ball, and this was after the heavy blow delivered by Clancy when he ignored the advice of his consulted touch judge Nigel Owens and called the knock-on after Parisse had released the hard-driving flanker Alessandro Zanni.
For a considerable while, though, England looked as if they might be beyond the help of such acts of charity.
It was just as well that Lancaster turned to Ben Youngs when Danny Care, a lively enough performer in England's period of ascendancy, seemed to be particularly unhinged by the new weight and passion of Italy. Care's skied kick allowed the Italians to set up a position of some menace and it was beautifully exploited by Italy's deceptively fragile outside-half Luciano Orquera. The Argentine-Italian floated a perfect kick into the path of the Australian-Italian Tom McLean for the only try, but if the origins of an achievement which England found quite impossible could hardly have had wider origins, it certainly represented some of the natural creativity of its adopted land.
When McLean, who also had an especially impressive game, went in the embattled Chris Ashton was nowhere to be seen. It was not the only example of a player's decline in assurance from his days of flamboyant swagger but then on this occasion he was hardly conspicuous in his apparent lack of self-belief. England passed the ball along the line at some speed but it was a velocity without either a change of direction or a touch of wit.
This was, naturally enough, a source of great encouragement for at least one Welshman. Jonathan Davies was quick to point out that when his compatriots had come under pressure at Murrayfield they had stuck it "to the guts" of Scotland. They had gone at the heart of their defence, which may not have brought a spectacular yield in points but, according to the great man, it was maybe an encouraging hint that they will be in the right frame of mind at the end of this week.
England, certainly, have to show some increased evidence of a killer touch of their own if they want to avoid the most crushing anticlimax. On a weekend seized by the force of Warburton, England were in quite desperate need of more conviction.
Lancaster has maybe enough reason to believe that he can still conjure a sufficient amount. But if bad days happen from time to time, the trick is to grow strong at those places which come under most pressure. For the new England that requirement was never more pressing than in the last few minutes yesterday. They survived, it is true, but by the barest margin. The Welsh were surely emboldened, by the old fire of Sam Warburton and his ability to exploit a weakness which had previously been so well concealed.
England v Italy in numbers
4: Line breaks by Italy yesterday, compared to one by England
19: England have beaten Italy in every one of their 19 meetings
14: Penalties given away by Italy yesterday, making it 43 for this Six Nations campaign in total