The recollection of an occasion when unbreakable spirit and total commitment won through against seemingly insuperable odds comes easily to him.
It has a familiar enough ring to it in the sense that Ulster go to Dublin today to try and take Leinster down in the Champions Cup quarter-final.
Leinster, the reigning European champions, in their own place, albeit the Aviva Stadium. Leinster, a star-studded squad who ritually swat Ulster aside when they venture south.
Gary Longwell knows exactly what it takes to shred the expected outcome from such events and he can readily empathise with the daunting task awaiting Ulster's players.
Just over 20 years ago he was part of the Ulster side which had to face down Toulouse in the European Cup quarter-final. Although the game was at the then Ravenhill, and Ulster had managed to already beat the powerhouse French club in Belfast during the pool stages, this time the visitors really meant business.
They came with a fully loaded deck and the implication was clear. Ulster had overachieved to reach the last-eight and were now about to be handed some serious punishment.
"They came with their top squad for the quarter-final and fully expected to win," says the now 47-year-old of what, of course, turned into an epic 15-13 win for Harry Williams' squad as they took a significant step towards that never to be forgotten January day at the then Lansdowne Road.
"There's a lovely photograph from that night and I remember seeing it in (team-mate) Tony McWhirter's house.
"There are about five Toulouse players lying on the pitch all calling for help from their physio and that just summed it up.
"We fired absolutely everything at them.
"We all just put our bodies on the line that night and if we hadn't we wouldn't have won.
"And that was the only way we could beat that team, everybody was fully committed to it (winning) and had to believe that we could do it," Longwell recalls of what was one of the internationally-capped second-row's best games during his lengthy tenure with Ulster.
There was a moment which has stayed with him since. As Toulouse mauled over the Ulster line to score, iconic French lock Fabien Pelous delivered a stark message to the prone Longwell (above right).
"He (Pelous) stood over me and told me, 'It's over, I tell you, it's over'. They certainly had that belief, but we had more.
"Everyone had to be at their very best to win it and I suppose it was about us being stronger as a group," adds Longwell, who is about to step away from the game after coaching junior club Randalstown for six years.
And, from downing Toulouse, we know what then went on to happen with that Ulster team and a certain piece of silverware.
Of more relevance to the here and now, the parallels of taking Toulouse's scalp in that epic backs-to-the-wall quarter-final when placed alongside Ulster's task today in crossing swords with Europe's current champions are not to be entirely dismissed.
Longwell, now a Performance Skills Coach at Sports Institute Northern Ireland, is well-versed in sporting psychology - he has a Masters degree in the subject - and reckons that a shock result is on if Ulster can bring unbreakable mental belief, and its obvious expression of physical domination, to the occasion.
And, no, this is not an evocation of the spirit of '99 and all that, simply the need for a group to stand tall and believe that anything in sport is possible.
The Ireland women's hockey side are a case in point. Through a connection with then coach Graham Shaw, Longwell worked with them in the lead-up to and during 2018's World Cup when, against all expectations, they made it to the final before claiming silver medals after losing to the Netherlands.
Another upsetting the odds achievement and Longwell was credited by the squad in helping with their mental approach to the intimidating task of performing at the tournament and overcoming the lingering issues of having missed out on the Rio Olympics in a penalty shoot-out.
"They were such a special group that they deserved a bit of success," says Longwell, who helped nurture some serious rugby talent - Lions Iain Henderson and Tommy Seymour to name just two notables - during his eight-year stint as High Performance Manager with the Ulster Academy after retiring from the game in 2005.
"It was fantastic to see the hockey girls achieve so much after being rank outsiders and it was very kind of them to mention me.
"But sport is about the players and what they do on the pitch.
"It's all about getting performance and how you deal with that," Longwell adds.
"It's about building a strong team and if that team is good with the psychological aspect of it, that will really help build that strong team.
"It's really helped my second career, if you like, in sports psychology having been through it and having seen where I failed and then also taking on board what things worked for me.
"In sport it's about decision making and how you are able to concentrate and cope with the pressure and stresses.
"It's not my job to solve athletes' problems, it's my job to listen to them and help them towards solving their problems," says Longwell, who lives in Jordanstown with wife Caroline and their twin daughters and son.
He actually turned out to be his own psychological coach back in the afterglow of winning the European Cup.
Twenty years ago, he realised that, eight years after having made his debut for Ulster, he was underachieving and essentially coasting.
A leaked fitness report from an Ireland camp saying as much hit him hard and he upped his commitment, big style.
Once more, with the odds weighed against him, he made a late arrival at Test level and went on to win 26 caps for Ireland and such was his determination that after a nasty finger fracture shipped at training in the lead-up to what would have been his first Six Nations start, Longwell seriously contemplated having the offending digit amputated in order to play.
"I wanted to play and that (losing the finger) wasn't really a massive decision for me," he says matter of factly.
"I thought it would just be a case of cutting it off but the surgeon refused and I didn't play.
"It was the little finger on my left hand which is now massively deformed anyway and I look at it every day and think, 'I wish I'd had that cut off'.
"You hear stories about, 'What would you give to play for Ireland?' and that was it. Like anybody, I just wanted to play and make any sacrifice."
'Boat' challenged himself to be better and made it that way both for himself and now others. Ulster need some of that today.