It's the question that has fried the brain and torn at the heart of every Scottish rugby fan - what does this team have to do to crash through the glass ceiling they have been hopping their heads against for the longest time?

On Saturday, at Murrayfield, they have another shot at the All Blacks - the 34th. They have had three near misses in a row under Gregor Townsend. Three wasted opportunities to beat the Kiwis for the first time ever.

"There's no magic pill," says Jack Dempsey, recently of Glasgow Warriors but now of Toshiba Brave Lupus in Japan. Dempsey is a straight talker. When you ask what needs to happen for Scotland to turn a corner once and for all, he does not mess about for long.

"It's probably two things," says the number eight. "Number one is momentum. There's momentum within games. We can be the best team in the world for 20 minutes and we can be the worst team in the world for 20 minutes.

"The Springboks are the flavour of the last eight years or so. They have a team that shows up every week and delivers and then they have a second team that does the same thing.

"The second thing is messaging. Can we stay stronger together for longer? That's what Sione [Tuipulotu] has been preaching. And what that means is, from a defensive point of view, can we make the team against us earn every single phase? Can we make it harder for them on every single phase?

"And then on attack, every time we hold the ball, we make it harder for the opposition. Can we do that on another level?

"If we just keep stacking those moments the habits will change. And then the results should follow."

Dempsey will play his 50th Test on Saturday - he has 14 for the Wallabies and this will be number 36 for Scotland.

His life is different now.

Based in Japan, he's available for all of the Nations Championship, unavailable for all of the Six Nations and then available again for the World Cup. That move to Japan, after five years with Glasgow, was one he thought about long and hard.

His mind was ever-changing when he was weighing it up, he says. He admits to feeling a little guilt over leaving the club that "resurrected" his career. Then there was the prospect of missing the Six Nations.

"You can be playing the Six Nations and be like 'this is the greatest thing, winning a Calcutta Cup'," he says. "All the other games as well, but mainly that one. You're like 'I'd love to drink from this cup every single year for the rest of my life'.

"I'd wake up one day and change my mind, wake up the next day and change it again. For me, it just came down to the cliche of only having one career. Let's try and do as much as you can.

"I've been so lucky to play Super Rugby, played for my home country, played for Glasgow and then played at Murrayfield. One thing I've learned in my career is that Murrayfield is the best place to play rugby, without a doubt.

"Every time you go to Murrayfield and play a game it's like it's your first one. You want to make sure that you don't take that for granted."

He will meet Dave Rennie again on Saturday. "We've had a chequered past," smiles Dempsey of the now New Zealand head coach.

Rennie didn't much fancy Dempsey when he was coaching Australia, describing the back row as lacking in physicality, something that could not be said of him in recent years.

"I wasn't in a great spot in Australia when he came in and gave me a kick up the arse, which sent me to Glasgow," Dempsey explains. "So in a way, you know, it really helped me.

"He's a pretty straight shooter, straight down the barrel. He'll give you some hard truths. He's a high-character guy, a highly successful guy. There's no bitterness there."

Saturday, he stresses, is all about those pressure moments and Scotland's ability to make life hell for Rennie's All Blacks.

"Not everyone gets what they deserve and not everyone gets what they should," Dempsey says.

Every win is hard-earned. A win against the All Blacks especially so.

More than 120 years since they first played the tourists, the chance has come again to beat them. The near-misses don't count for anything more.