McGeechan placed a great emphasis on a sense of freedom and responsibility prior to and during the 10-match tour of the Republic and, for Vickery and his Lions team-mates, it was the perfect platform to challenge the World Champions in their own backyard.
"Just because you're pro, it doesn't mean you have to starve people of what makes them feel good," the 33-year-old, who knows McGeechan better than most having played under the Scotsman at London Wasps, told the Unofficial England website.
"How do you get the best out of people? By getting the right balance.
"The nice thing about a Lions tour with Geech and Gerald (Davies) in charge was that, with them, you don't have to be things like completely teetotal. If someone wants to have a drink, a glass of wine, a meal, wants to go see family, then that's fine.
"As long as you do your training, prep work, and play well they had no problems. We were basically treated like adults. Why should it be different to regular working life?
"That's what Geech does, he trusts you to do the right thing. Everyone respected him for that, and respected the rules and what was expected of us. It wasn't like being in a classroom and treated like kids. It was nice and refreshing to deal with people who wanted the best for you."
Having toured Australia with the 2001 Lions, Vickery understands the commercial and marketing responsibilities that come with being selected to represent the world's most-famous touring team.
He also understands why such a great emphasis is placed on team-building exercises when a squad of close to 40 players have such a short time to bond.
But the ex-Gloucester stalwart believes that the key to a successful Lions tour is adapting to what's in front of you, with coaches listening to players, and vice versa.
In 2009, that was exactly what happened under the stewardship of McGeechan and Davies.
"What Geech made a conscious effort to do was to get all the commercial stuff out the way as early as possible in the week before we went away," explained Vickery, who won a further two Test caps this summer having started all three internationals against the Wallabies eight years ago.
"He wanted to try and do everything early, so that afterwards we could focus on the rugby as much as we could.
"I remember we had had a long day, with lots of publicity and press stuff going on. After we finally got back, everyone was knackered, and we were scheduled to leave at seven the next morning to go sailing for team bonding.
"I was rooming with Donncha [O'Callaghan] I think it was and we got a text saying that sailing was cancelled and we'd just be in the bar having a drink. We thought it was a wind up. Funny thing was it ended up being true, and we all ended up in the bar that night.
"Without wanting to knock team-building exercises, a glass of beer, the whole lot of us chatting, getting to know each other was fantastic. By the end of the night, bearing in mind this was on day three or four, everybody had had such a good time, got to know each other really well that the next day we were all set and ready to go."