That is the question the Scottish Rugby Union board must ponder as speculation mounts that they may take the easiest – and perhaps cheapest – available option by appointing Scott Johnson on an interim basis.
So much so that the Opsreys veterans of that surprise Welsh success in 2005 are understood to have been influential in persuading the province's management to bring Johnson there in 2009.
He got off to a decent start with them, but it is also felt in Wales that the longer Johnson was there and the more power he was given, in moving from the post of coach to director of rugby, the less effective he became.
In the end, there were few tears shed around Swansea and Neath when it was announced late last year that Johnson was leaving at the end of the season to join Scotland.
His departure was ultimately accelerated and, again, it is impossible not to identify a direct correlation between that happening and the Ospreys' rise from mid-table to claiming the RaboDirect Pro12 title.
Johnson first gained notice as much as 11 years ago when he was backs coach to the Australia A team that derailed the British & Irish Lions who, until that point, had looked odds-on to win their Test series against the Wallabies but instead lost it. It was with Wales that he really emerged, cutting a rather eccentric figure on the sidelines when he joined the staff, but receiving huge credit for improving the skills of the players who produced stunning handling performances in brave defeats to the All Blacks and England at the 2003 World Cup when Steve Hansen, the current All Blacks head coach, was in charge.
That proved the foundation for what happened two years later when they won the 2005 grand slam and it must be stressed that Robinson is by no means the only top coach in the sport to have been impressed by Johnson during that Lions tour. It was Graham Henry, head coach of that party, who brought him to Wales.
However, following the 2005 grand slam came intrigue, with all sorts of murmurings about the shenanigans surrounding the extraordinary way Ruddock was removed from his post as Wales head coach while they were still defending a Six Nations title no-one had anticipated them claiming.
The extent of any role Johnson may have played in undermining Ruddock is ancient history but when Robinson departed at the weekend, after the pair had worked together for just six matches, Oscar Wilde's words sprang to mind: "To lose one parent may be regarded as a misfortune; to lose both looks like carelessness."
It is actually the fourth time Johnson has seen the head coach of a national team depart not long after he joined him since Henry went soon after bringing him to Wales, while John Connolly brought Johnson home to his native Australia ahead of the 2007 World Cup, only for them to be removed after overseeing the Wallabies' worst World Cup campaign for 20 years.
Perhaps even more relevant, then, is another saying, which originally came into common usage in sporting circles, that it is better to be lucky than good.
In that regard, Johnson might also want to consider what he has done to bring about the sort of bad luck that seems to follow him, or at least those for whom he works, albeit he does not give the impression of someone who wastes too much time dealing with mirrors.
In more serious vein, though, he gained further experience as a national team head coach in a brief spell with the USA, in which he lost five of six matches in charge in 2008.
Yet Johnson's departure from that job was his choice because it was at that point that the Ospreys approached him. His popularity with the top Welsh players of that era was also demonstrated by the fact Cardiff Blues, the other most affluent Welsh province, approached him to join them before he went to the US.
Every indication has also been that Scotland's players have enjoyed working with Johnson over the past six months, but Gregor Townsend was also popular in spite of his ineffectiveness as Johnson's predecessor as attack coach. It is a long-established fact that assistant coaches can stay closer to players than those who have ultimate responsibility for team selection.
Perhaps the biggest thing the SRU must consider, then, is that for all that Johnson clearly has the capacity to help Scotland's players get better at their jobs, it is another matter having the vision required to understand what is necessary to get them winning games until their skill levels have improved.
In that context it is worth remembering that he took up his post just five months ago, having presumably signed up fully to Robinson's vision of the way forward, to which he would have been expected to be wholly committed. If so, it would seem remarkable if he now had an alternative plan in mind that would allow him to make the tactical and stylistic changes that are clearly necessary.