Never go back.
It is one of sport’s most classic nuggets of received wisdom and football, in particular, has witnessed more than its fair share of unhappy reunions down the years.
A penny for the thoughts of Scotland fans, then, after the news that Alex McLeish is back in the hot seat of the national team more than a decade on from his first stint in charge.
That spell ended in acrimonious circumstances as he accepted a lucrative move to Birmingham City following an impressive, if ultimately unsuccessful, Euro 2008 qualification campaign.
Critics have labelled his succession of Gordon Strachan a retrograde step, the unsatisfactory culmination of a ham-fisted, drawn-out recruitment process that saw the SFA eventually snubbed by their first choice, Northern Ireland boss Michael O’Neill.
Certainly the man himself does not agree with such assessments. There was a glint in McLeish’s eye at his official unveiling on Friday as he spoke of “fate” bringing him back to the job.
While admitting that the SFA’s handling of the succession plan has been a “shambles”, he explained how McLeish will breathe fresh life into the Scotland setup after the spikiness and tension that characterised much of the Strachan era.
“He’s a terrific guy, a guy I know really well,” said Currie in an exclusive interview with BTSport.com. “He loves the game. You cannot question his enthusiasm levels.
“So from that point of view we’ve got a guy who’s going to come in and galvanise the players who are available to him right now. He’s going to create a good team spirit, a good spirit in the dressing room.
“You talk to just about all his former players and they loved working under him. I think he is going to be brilliant for the players.
“There’ll be a lot of people wondering if this is a panic appointment after a recruitment process that went on far too long.
“I hope Alex McLeish proves them all wrong.”
And how will he differ from Strachan in his approach?
“He’s going to be very different from Gordon, who had a very mixed relationship with the press,” said Currie.
“Gordon is single-minded. He would probably admit himself he is a very stubborn guy. He refused to pick some players and the press didn’t like it.
“At the end when Celtic were doing particularly well in Brendan Rodgers’ first season, it took him a while to pick guys like Kieran Tierney. Stuart Armstrong was overlooked for a while and came in and has been man of the match a couple of times.
“I don’t think Alex will have that stubborn streak. He will be open-minded.
“Another criticism of Gordon is that he didn’t pick enough players who were based in Scotland because he didn’t watch enough football up there.
“Alex, I imagine, will take all of that to heart and he will be getting himself to the games. He knows the English market, he’s got brilliant contacts down there, and he knows so many people who are still in Scottish football.
“He is going to have a much better relationship with the press – if he wins, of course – and they’re probably going to take to him because he is more open and less guarded.”
McLeish has endured mixed fortunes since quitting the Scotland post in November 2007, with his stunning League Cup success with Birmingham in 2011 being offset by relegation from the Premier League three months later.
Difficult spells with Aston Villa, Nottingham Forest, Genk and Zamalek followed and before the SFA came calling he had been out of work since departing the Egyptian side in May 2016.
Currie admitted he can understand why people will use McLeish’s record as a stick to beat him with, but pointed to the achievements of his first spell – such as James McFadden’s famous winner against France in Paris - as evidence that he is up to the job.
“He took on some hard tasks. If you look on paper, there’s a few situations there that weren’t great for the manager and that’s why there are people doubting, at this point in his career, whether he’s the right man for the job,” he said.
“From my point of view, you need to look at the positives and that’s all we can do right now because he’s appointed.
“He’s got the best win percentage of any recent Scotland manager. We’re not talking about the type of group Scotland were just in, when they had the likes of Slovenia and Slovakia.
“OK, England were in there as well but he had to face a group where they had France, Italy and Ukraine as the top three seeds and Scotland came within 45 minutes of qualifying.
“You can’t knock what he’s done before. He’s proven in the past that he can get a team of Scotland players together to take on some of the best teams in the world and he can produce results.
“We have to remember that is what he was once capable of. Once upon a time, as a result of that campaign, his managerial stock was sky-high.
"Let’s hope that by the end of this next spell he takes us to the next finals in 2020 and his stock is sky-high again.”