Had the Priory Clinic set up a temporary outpost at Murrayfield?

Watching Scotland's victory over Italy there last weekend, you might have been forgiven for thinking so, as the match restored so many reputations it was more of a rehab job than anything else.

There was big Jim Hamilton, responding brilliantly and bruisingly to the challenge laid down by the coaches. There was Ross Ford, maybe not the force of old, but still reaching a level he had not visited for more than a year. And there was Ruaridh Jackson, pulling the strings, ushering his backs into play and acting throughout like a proper, grown-up fly-half.

The very same Ruaridh Jackson, in fact, who had delivered a largely anonymous performance in Scot-land's loss to England a week earlier. But the Twickenham display was far from being the nadir in the recent personal history of a player who, having announced himself with a wondrous performance on his Glasgow debut against Bath in December 2008, has spent the past four years struggling to convince doubters that it was anything but a one-off.

The graph of his career since plots a rollercoaster ride between such peaks as being anointed as Scotland's first-choice playmaker ahead of the 2011 World Cup and such troughs as being left out of the squad chosen to tour Australasia eight months later. Chuck in a few injuries, crises of confidence and wayward kicking episodes and you start to understand why, at the tender age of 24, the former golden child was being described as a has-been in some quarters and a never-will-be in others.

The birthday counter clicked again last Tuesday, taking Jackson along to the quarter-century mark. Still a bit young to start penning his memoirs, but an apposite moment to pause for reflection all the same.

So how different is the Jackson of today to the young man who made his Scotland debut as a replacement against New Zealand in November 2010 and then kicked a dramatic winning goal against Samoa two weeks later? "I think I've not necessarily changed wholeheartedly as a player," Jackson replies. "But I've certainly learned a few things and I'm certainly stronger mentally with what I've been through in the last couple of seasons with injury, dips of form, being in and out of squads.

"Now I've got this chance again. I'm not wanting to rest on anything. These experiences over the last couple of years have shown me that there's competition coming up from below, I can't relax and I've got to keep improving. I've got that hunger now and I want to stay in that jersey and keep kicking on."

You can sense the urgency. Quite a few of the Scotland players who beat Italy eight days ago have said they would have preferred to play again this weekend, keeping the confidence and momentum of their 34-10 thrashing of the Azzurri and taking advantage of the fact that Irish morale could be low after their drab performance against England last Sunday.

Like many in the Scotland squad, Jackson's first reaction to the sprightly performance against Italy may well have been to heave a sigh of relief. Interim coaches Scott Johnson and Dean Ryan had dropped heavy hints that changes could be in the offing, and that there were players ready and willing to step into the places of those who had underperformed at Twickenham if sudden improvements were not made.

"It was never said internally that that would happen but you do worry," Jackson says. "If you're not winning games then things generally have to change. They have to look elsewhere and as players we have to take that responsibility on ourselves. If we're not performing then ultimately it's our fault.

"I don't think it was as simple as 'If you lose this game you're all gone', but there probably were a fair few heads on the block who could take the blame. Everyone was wary of that and we just wanted to get back to winning ways – and gladly we did it in good style."

And yet Jackson plays down the fear factor. Under Andy Robinson, there was a suspicion that players had become inhibited, not scared of the selector's axe, just wary of doing the wrong thing. Towards the end, they were playing joyless, stilted rugby. In their loss to Tonga in November, the result that ended Robinson's reign, they seemed like rabbits caught in particularly baleful headlights.

Jackson can at least be absolved of responsibility for that calamitous result as he had already been dropped from the squad. That weekend, he played for Glasgow against Leinster, turned in a nondescript display in the Warriors' 6-0 loss at Scotstoun, and was dropped the next weekend. A week later, he was playing for Dundee in a club match, a startling sequence of affairs for a player who had faced up to the All Blacks three weeks earlier.

No disrespect to Dundee, but Jackson bottomed out there. "It's not what you want," he says. "I wasn't in the best of places after getting dropped from the Scotland squad and then that Leinster game. There was nobody really watching [his Dundee game] and it was just a matter of going out, playing rugby and enjoying it."

And, for the first time in a long time, that is just what he did. They say you should dance like nobody's watching, so Jackson made the most of his temporary departure from the limelight. Confidence and appetite restored, he was in the Glasgow side who took Castres to the wire in the Heineken Cup on French soil the following weekend.

Jackson watches his words carefully, but it is easy to sense that Robinson's famous intensity had an inhibiting effect on players in the Scotland camp. The jury is out on whether it is the arrival of Johnson or the departure of Robinson that has had the greater effect on the Scotland squad's spirits, but Jackson makes it clear the mood has changed radically.

"Everyone knows Scott is very jovial, and some of the stuff he comes out with seems strange at times," he says. "But there is always a method to his madness, whereas Robbo maybe seemed a lot more serious all the time. Johnno has come in with a good, fresh approach, and said, 'Let's get back to enjoying it. Let's enjoy each other's company and get some unity back, and really just go out there and fight for everything'.

"If you play well the results will come, and we're buying into that. Hopefully in the next game we can kick on again. We don't want that one result to be a flash in the pan."