McInnes made his mark after he left Tannadice in 2006, returning to Scotland and St Johnstone a year after a shift in the midfield of Millwall's Den where he had continued his learning process.
His friendship with Archibald, however, remained firm and none was happier than he to see the former defender sit in the dugout at Partick Thistle once Jackie McNamara had decamped to Tannadice.
On Saturday, the pair will be in opposite dugouts as McInnes' Aberdeen, still to find consistency in these embryonic stages of this season, pitch-up at Firhill for the first time this term and seek to make a more significant impact than some other sides have done against the prickly hosts, who lie a point above them in the SPFL Premiership table.
Doubts may have been cast on Archibald's ability to assume control at Thistle, especially as he had been McNamara's assistant for only a short time before change was thrust upon him in the latter stages of last season, before all ended happily with their promotion to the top flight.
"Alan's made a brilliant start," McInnes said. "He's really ripped the manual up. Most folk have a blip at some point after taking charge, but, apart from maybe the Challenge Cup final [Thistle lost to Queen of the South on penalty kicks], it's all been going well.
"He's a guy I speak to on a regular basis. We used to travel together at United and he's a good friend. I am delighted to see him taking so well to management."
So what was it that shone through during those trips between Glasgow to Tayside that persuaded the former Rangers and West Brom playmaker that his friend and team-mate would one day make the grade as a coach?
"He was always a good professional who spoke well about the game," McInnes recalled. "He was always perceptive about how games are won and lost and I enjoy talking football with him.
"It would be wrong to say it's not a surprise that he's done so well, because it has been such a strong start to his managerial career, despite difficult circumstances.
"There was pressure on him to continue the good work of Jackie. It could have gone either way, but if anything Thistle have got even stronger.
"That will be the pleasing thing for him. He's gone with the same team which won promotion probably 95 per cent of the time and the signings he brought in over the summer are struggling to get in the team because they have been so good.
"He even had to overcome the loss of two of his best players in Paul Paton and Chris Erskine [both now at Dundee United].
McInnes knows all about the pitfalls of moving from coach to manager within a club. When he succeeded Owen Coyle at St Johnstone, however, he took them into the top tier of Scottish football within two years and was instrumental in laying the foundations which have seen the Perth club establish themselves in the Premiership.
"There is always a difficult transition moving from being a coach to taking charge," he insisted.
"Partick are a great story and Alan and Scott Paterson [the assistant manager] have done a great job there.
"There's always a feelgood factor when you come up. You're used to winning, the crowd are with you and there is an inherent confidence.
"The crucial thing is how you react to disappointments and losing games, but they have only really had that against Motherwell."
Aberdeen need to convince their fans that the revolution always anticipated when a new leader arrives - McInnes is their fifth manager in the last decade - is still on course.
Meanwhile, the McInnes-Archibald old pals act will be put into abeyance on Saturday, at least for ninety battling minutes.