Much has happened, of course, to David Goodwillie in the 8½ years or so since he first convinced his then manager, Gordon Chisholm, that his age was no impediment to his ambition and took his first-team bow as a substitute at Ibrox.
Court cases, six months in limbo in 2011 before rape charges against him were dropped, and a £2.8m move to Blackburn Rovers that brought little other than chaos and relegation as well as a short, ill-fated spell farmed out to Crystal Palace undoubtedly took some kind of toll.
By the time Goodwillie had returned to Tannadice on loan for six months at the start of last season, he looked a different player. He did manage half-a-dozen goals, three of those coming in the same game against Partick Thistle, but he was largely unimpressive, with Stephen Thompson, the chairman of United, revealing the club made no moves to extend his stay as a result of his form being "a bit of a disappointment".
McInnes sat down with Goodwillie, who ended last term on loan at Blackpool before agreeing to terminate the remainder of his contract at Ewood Park, at the end of last week to get some kind of handle on where he is professionally, personally and psychologically.
There have been whispers around the game that the 25-year-old has lost his appetite, lost the drive that made his progress into the United team as a teenager almost inevitable. McInnes, to his delight, saw none of that.
Indeed, he recognised flashes of the kid he got to know and love during his days as a senior player at Tannadice and he has made it clear he wants Goodwillie to bring that infectious personality of his youth back to the table when he steps into the locker-room at Pittodrie.
Playing with freedom on the field is one thing. McInnes' plan to rehabilitate Goodwillie is based on much more than that. He wants to give him the freedom to be himself.
"I met him last Friday," said McInnes. "I always meet a player before I sign him and it has a lot to do with your gut feeling. Players, of course, can say all the right things. You just hope it rings true.
"I do believe there is a hunger there, though. I do believe, at 25 years of age, that he has too much football ahead of him to be anything other than hungry and motivated.
"He has a point to prove as well. I want him to come in to what is a brilliant club to work for and really show his personality. I remember him at Dundee United when he first came into the team. He was confident, cocky and sure of himself. I want that personality to be within our dressing-room.
"When I first met him, he was still a young boy, albeit one that was very highly thought of. As a senior player, I was really fond of him and his personality and always believed he could do well. I liked the way he backed himself and he just has to back himself now again. Rather than get too hung-up on things, he just has to go out there and play.
"I know our boys will love him. We will put the demand on him to work hard and I hope he can take the chance we will give him."
McInnes accepts Goodwillie, eligible to play in the Europa League second round qualifier against Groningen should Aberdeen successfully negotiate Thursday night's visit to Daugava Riga, may need more of an arm round his shoulder than most in the early stages of the campaign.
However, he does not want Goodwillie's past problems to hinder his future. "Have we got a bruised player? Possibly," said McInnes. "You can overanalyse all that, though. Every player is important to us and we feel we have to be close to them all and put work into them all. David probably needs that more than others at this moment, but I just want him to be himself. He will get every opportunity to do that. We will look after him, he's one of us now, and his team-mates will look after him. I really don't want him to think too much about it. If he works hard, I am sure it can work for him and be a good move for him."
Indeed, McInnes has made it clear he expects Goodwillie to be looking towards rekindling his international career having earned the last of his three caps in a 1-0 European Championship qualifying win over Lithuania at Hampden in September 2011.
"All managers are interested in players scoring goals regularly," said McInnes. "He is good enough to score goals on a regular basis and I am sure that is something that is on his mind as well. I would certainly hope it would be. At 25, he still has so much to do.
"David has not had a lot of stability in his career over the past couple of years. Whether it was the fault of others or not, he is still, for me, a player with the capability to do really well. I was a team-mate of his and my assistant, Tony Docherty, coached him. We always felt that he was a player that could go on to have a top, top career.
"Maybe he went to the wrong club. I think he would also be the first to admit that he has made a few mistakes along the way, but he is 25 years of age and we feel this is a signing worth making because of what he can be."
McInnes, meanwhile, has revealed that Peter Pawlett, injured in the 5-0 win over Daugava Riga last week, is in contention to return for that likely match-up with Groningen.
"Barring a miracle, he won't travel to Latvia, but the ankle is improving and we hope he will be available for the next game if he doesn't make the one on Thursday," said McInnes.