We got on wonderfully well during my time there, but he couldn't help but have a little, friendly dig amid the jubilation at full-time at the William Hill Scottish Cup final yesterday when he came up to the press box at Celtic Park where I was commentating for radio.
"I spent a fortune on you all that time ago," he said as he looked around the stadium, with blue-and-white confetti scattered all over the pitch and the old trophy in the hands of his players. "And you couldn't deliver that for me."
It was lovely to have a laugh together again, even if it was at my expense. I am so delighted for Geoff and his family that they have experienced the joy of such a momentous triumph at last.
Geoff ended up making a bit of profit on me when he sold me to Aberdeen and he has always run St Johnstone in a sensible manner during a period which has seen a number of their rivals slide into administration and debt.
He passed the chairmanship on to his son Stevie and he has carried on in the same vein.
Geoff and I sat down regularly when the team was away on trips to talk about his passion for horses. He knew I liked the racing as well and we talked about owning horses together. The bottom line, though, is that we got on so famously because he is such a down-to-earth man and his son is the same.
When you work at things and don't get the success you want over the years, you deserve to relish every single second of it when it finally arrives at your door.
Something told me St Johnstone were destined to win the cup. I had always had it in my mind that fate would be the defining factor in ending their 130-year wait for a major trophy, but I was wrong.
What actually ended that long, painful drought was a team of players who were absolutely magnificent throughout the final. There wasn't a single player in the starting XI that you could find fault with and the two substitutes came on to play their part to perfection as well.
United supporters will be disappointed with their team's display. They created chances, but they did not play well and that is largely because St Johnstone did not allow them to play the way they wanted.
I thought United would dominate midfield. They effectively play five men in there and I thought that would give them the advantage over the four of St Johnstone, but it was Saints who dominated the central area.
United ended up playing long balls to Nadir Ciftci and, for me, they were forced into it.
St Johnstone pressed from the front with their two strikers pressurising the back four and they kept it nice and narrow in the middle.
The four boys in there worked their socks off and the two full-backs, Dave Mackay and Brian Easton, did an unbelievable job by going high all game and pushing up to threaten the midfield. They did so much to cancel out their opponents.
So much will be said, when reflecting upon this fairytale, about St Johnstone's players working hard to make their way in the game. Almost all of them have had setbacks and stories to tell.
We should stop focusing on that. We should stop underplaying their achievements, dismissively labelling them as good club pros. These guys are really, really good players. They could not have achieved what they have this season, in the league, in Europe and in the cups, without being talented.
Under their manager, Tommy Wright, they have taken the club to a whole new level.
Wright took a little gamble by going 4-5-1 with 15 minutes to go to see out the game, but it paid off. He knew what he was doing and you cannot underestimate the job he has done alongside Callum Davidson.
No-one should begrudge anyone at St Johnstone their celebrations. Their success is wholly merited from the top of the club down.