Warren Gatland will on Saturday reach 100 Test matches as Wales’s coach. He will get to the landmark 20 years to the day since he took over from Brian Ashton in charge of Ireland: his sacking three years later, in circumstances that read like something from a spy novel, remains the low point in his career, a blot all his success since has not entirely erased.

As the amateur era drifted to its end, the winner of the match between Ireland and Wales tended to avoid the wooden spoon. Between 1986 and 1995 there was only one year when one of them (1994, when Scotland broke the monopoly) was not last or joint bottom. The last time one of them finished below the rest was Wales in 2003 and for most of this decade they have finished in the top half of the table.

In 10 Six Nations campaigns in charge of Wales and Ireland to date, Gatland’s teams have finished first twice, second twice, third three times and fourth three times. He has operated without the playing and financial resources of England and France but despite Wales enjoying their best period since the 70s, admiration in his adopted country tends to be grudging at best.

It may have something to do with the pragmatic style of play he fostered, rugby without a smile. Never mind the largely infertile years of the 80s and 90s, in a land of romantics weaned on tippy-toed tormentors there is a certain way of winning, never mind Wales have always been capable of reductive rugby in the pursuit of victory.

Gatland will leave Wales after next year’s World Cup with praise rather than fanfare or even gratitude. When asked this week what advice he would give to a young coach, he replied: “Do your best to deal with the media as positively as possible. That’s been my downfall; you live and learn.”

Perception. Wales’s first New Zealand coach was Graham Henry, a more avuncular Kiwi who was hailed as the great redeemer, indulged even when the walls started to fall in. He was succeeded by Steve Hansen, a former policeman whose default facial expression was a no trespassing sign. He made no effort to cultivate the media or his own image, fixated with turning round a vessel heading in the wrong direction.

Gatland is of the same mind, unswayed by opinion from the outside, although frustrated by misconception. The media are an occupational hazard to be used but kept at a distance. He is not one to be diverted from the path he has chosen and his strength of character has been adopted by his players. A team who before his time were renowned for flakiness and unreliability now take some beating.

Gatland is one of a small number of elite coaches in the game; experienced, hard characters who shield their players from outside noise and absorb criticism – Hansen, England’s Eddie Jones and Ireland’s Joe Schmidt are of the same mould. Australia’s Michael Cheika is not quite there, lacking the touch in selection of the other four and occasionally volatile.

Vern Cotter (surely a candidate to succeed Gatland) was getting there with Scotland last season but was let go by the governing body which wanted to promote one of its own, Gregor Townsend. As he prepares for his first Calcutta Cup match as coach, the former Lions’ fly-half faces a test of his mettle. Scotland’s opening weekend thumping in Wales was followed by victory at home to France but England will not be so accommodating should they take a 10-point lead.

Townsend wants Scotland to play with vim and vigour, like Glasgow did under him, possessing a capacity to create something out of nothing in broken play. Finn Russell at No 10 personifies Townsend’s approach, constantly trying to make something happen, but after one poor performance and another mediocre one, the coach has come under pressure not to overindulge his playmaker.

The optimism spawned in Scotland after an autumn series that included a crushing victory over Australia and a narrow defeat to New Zealand has faded in the harsher environment of tournament rugby. The spotlight is on Townsend – Gatland, Hansen, Jones and Schmidt would not blink but trust what they had put in place, hardened by experience.

It is 10 years since Scotland defeated England, and since the Six Nations started they have scored only two tries against them at Murrayfield, the last in 2004. While the score in Wales was embarrassing for a side who harboured ambitions of winning in Cardiff for the first time since 2004, Scotland had more of the play in the opening half but gave away the opening try and failed to take three prime opportunities. They were not blown away as they were at Twickenham last year.

This is when coaches earn their money and establish their reputations. If he believes in Russell, it does not matter what those on the outside think.

Hansen endured a long losing run with Wales in 2002-03, Jones’s time with Australia ended in a series of reverses and Gatland was fired by Ireland. They were all fortified by setbacks, stiffened by an inner resolve.

Gatland will take some replacing by Wales. He has asked a lot of his players, as Schmidt has of Ireland’s, and Saturday’s match will be a typically all-in encounter between sides who are soft touches no longer, driven by exceptional coaches.

• This is an extract taken from our weekly rugby union email, the Breakdown. To subscribe, just visit this page and follow the instructions, or sign up below.