Interesting take a couple of factors not considered.
The quality of non-Blues NZ teams change drastically. For example during Lam's 2010 tenure the Chiefs and Highlanders were bottom four on the table.
Umaga has the toughest job because the most damage has been done before him. A quality coach could have turned around things straight after Nucifora went sideways, but the tenures of Kirwan and Lam have done such damage to the culture and reputation of the club the task in front of Tana is harder than Lam who was at least handed a professional sporting team.
That doesn't excuse Umaga - he was handed the team in such poor condition that the bar of initial success was lower than it was for any of the others too, and he is struggling to make it.








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