I suspect one of his qualities as a coach is that he can quite easily terrify players. Sometimes, particularly when the topic is the opposition or competition generally, he appears to be slowly munching on a wasp. You can see the suppressed aggression there which I'm sure he lets explode when a little encouragement is needed.
He never got an All Black full cap over a period of literally years as an understudy to the indestructible Sean Fitzpatrick and this must have something to do with it - all that frustration to work off. But what makes him very special is that he can also be a very sensitive and understanding man-manager. His exemplary nurturing treatment of Gavin Henson - who I don't think has ever been managed so well - is testament to that.
BTW there's a fantastic compilation on YouTube of highlights of the Welsh team in the 80s. Despite it not being a vintage era overall, I'd forgotten the truly beautiful rugby played by the Triple Crown winning team of 1988. At one point they had four fly-halfs playing in the back line, each of them consummate playmakers, particularly the extravagantly talented Mark Ring. The revelation to me, though, was just how good Richie Collins was - fantastic hands and acceleration. I think he played basketball for Wales and it really shows. Here's the url: http://uk.youtube.com/watch?v=vjs62E6zovo.