That goes some way to explaining Gatland's decision to sign on as Wales coach until 2015. He has a young team who are potential world beaters in four years as well. For New Zealanders, Gatland could be the one that got away.
He could also be excused for some sense of satisfaction in beating Ireland. He coached the greens from 1998-2001 when he was ousted in a political coup by his then assistant Eddie O'Sullivan, who himself was later sidelined in favour of current coach Declan Kidney.
Gatland's first World Cup, in 1999, ended badly with Ireland not making the quarter-finals, losing to Argentina. This World Cup has been rather different.
The sense of resolve under Gatland was best demonstrated by Wales' discipline and defence, particularly in their own 22. Yes, Ireland opted out of taking three potential kicks at goal and eventually slotted one but Wales tackled relentlessly without the urge to slip rogue hands into the ruck or come in from the wrong side.
"We were under pressure several times, particularly in that first half, and the defence was outstanding," Gatland said. "We tried to take the feet out from under those strong Irish ball carriers."
A trademark rush defence, where some might claim they pushed the offside to its limit, also reaped rewards.
What is also impressive about Gatland's reign, which began with a Six Nations victory in 2008, is his loyalty to the current young crop. He has a nurturing touch.
"They have no baggage; no fear factor," Gatland said. "We're in New Zealand, not in the bubble of Wales. While we're here, we don't have to listen to the pundits spouting negativity each day. I don't think any team would have worked as hard pre-season. We had guys throwing up doing stuff in the sand dunes. These guys went through some pain. That galvanises a team."
There was one injury concern for the Welsh. Lock Luke Charteris took a knock to the shoulder. He was in a lot of pain without much strength after what Gatland described as a "phenomenal work rate and tackle count in the first half". He will be reassessed today.