Fact: at the end of the 2011 World Cup New Zealand had one top-notch fly-half and had taken the title, without him. Now they have four or five and by the 2015 championship the queue could stretch around the block. At the end of their 2011 World Cup England had no settled centre partnership; the situation is much the same today.

Fact: Courtney Lawes has just come through a brilliant autumn series, but it's taken him four years and 23 caps to become an overnight sensation. For New Zealand, Brodie Retallick is in the same position a year after making his debut. Why?

I wouldn't pretend to have all the answers, but as a Bay of Plenty old boy circa 1990, I have ideas about why New Zealand shouldn't be embarrassed to call themselves the most dominant team in the world and why they have gone a year unbeaten and are likely to stay that way after Sunday's game in Dublin.

First, though, you have to understand how a callow 21-year-old second-row found himself in New Zealand; well, after two broken arms in two seasons with Wasps, I was desperate for rugby and my club coach, Mark Taylor, a former All Black, had pointed the way to Ngongotaha rugby club in Rotorua.

If a season of club rugby in New Zealand seemed just the ticket, doubts set in quickly. First, a relative of my soon-to-be wife, another former All Black, asked: "Why Rotorua?" – suggesting that even Kiwis thought twice about playing rugby in the Bay of Plenty area. Not for nothing were they traditionally given the job of giving tourists a good seeing to before their first Test against the All Blacks.

Second, my first experience of New Zealand club rugby – watching a game of park football in North Harbour – gave me an idea of the standard I was about to confront in my first game with Ngongotaha. It was pretty stiff competition and more to the point it was pretty lively.

For a start, there were only two of us – the locks – who weren't Maori and when things kicked off between me and a former All Black second-row, it was fairly obvious that I was on my own. Over here these things have a bit of structure; everyone gets off a few, very few land, and you fall on top of each other. That day the ref was a long time blowing his whistle.

In fact after three or four weeks I was prepared to call it a day. Six months of finishing each weekend black and blue was not what I wanted, but suddenly it came to an end and from then on, every time their 6ft 6in Brit got picked on, Ngongotaha waded in. It was like some rite of passage was over and invites to Maori barbecues followed. My folks were loaned a house on the lake for the wedding. We even had the use of a boat and with every day came the gift of a huge lake fish.

More important, Bay of Plenty heard about the Brit with Ngongotaha, one of about 36 quality clubs in the region and a season with the NPC followed. As did a win over the touring Wallabies and an invitation to fly from Auckland to Argentina to join up with England and the likes of Jason Leonard, who was also about to make his Test debut.

The guy who left England for New Zealand might not have coped, especially when things got pretty lively in Tucumán, whereas the 21-year-old who had played six months with Bay of Plenty knew what it was about. New Zealand rugby changed me and that's the point.

When Brodie Retallick, another Bay boy, became an All Black it was on the back of an unrelentingly tough rugby education. With the Steamers, his club, Retallick wouldn't have found life easy even with his talent. Bay of Plenty would have been tougher again and from there to the Chiefs in Super Rugby the pace of the game would have changed again. But from school to club to All Blacks is a natural progression.

Over here it's tough at the top, but only at the top. Below the professional ranks attitudes and expectations are distinctly amateur. True, there are thousands upon thousands playing rugby, but it's not the rugby played the New Zealand way. When did we last see a Retallick or a Charles Piutau, a product of Pakuranga in Auckland, burst on to the scene and look so immediately comfortable in Test conditions.

True, we have the biggest rugby-playing population in the world, but the base of the pyramid which leads to Test rugby feels a whole lot narrower than it did in Ngongotaha.