Mystic raises the objection that Jeremias' ratings are suspect inasmuch as they fail to incorporate player-aging effects. True enough. But I think that this effect, taken into account, would serve to compress the range of results. Tom Thibodeau, table-topping rating, must be biased upwards for having inherited a very young team.
The apparent fact of the matter is that "head coaches" (coaching staffs, really) aren't that important in the grand scheme of things. Furthermore, on average, this collective input into the NBA production function appears to subtracts value.
If you take J.E.'s numbers and weight by games played, the average coaching staff's RAPM is -0.5. And were one to average by possessions, my suspicion is that the rating would be a bit lower still (as slower pace is probably correlated with better coaching performance). And this (non-positive) result should be robust, given that it is based on 10 years' worth of data, no?
So, Crow, courage! I would basically take J.E.'s results at face value in such discussions. They are at least a good starting point for conversation and provide very useful perspective.
Consider the most recent case in point, where Portland after what was surely much due diligence hires Stotts (-1.9) to replace McMillan (-1.1). Stotts' previous head coaching experience: with Atlanta, where he replaced Lon Kruger (-1.4) and Milwaukee, where he replaced Porter (-0.7). Good stuff!
And what do we learn from the experts, commenting on the hire (http://espn.go.com/nba/story/_/id/82454 ... head-coach
"Terry is one of the elite offensive minds in the NBA, has extensive experience with multiple organizations and was instrumental in the Dallas Mavericks winning the 2011 NBA championship
," general manager Neil Olshey said.
Stotts' Offensive RAPM -3.1. 10 year average Offensive RAPM -1.3.
Maybe he's improved of late.
"He has coached under Rick Carlisle the past four seasons. In a recent interview with The Oregonian, Carlisle said: "Of all the coaches presently in play, Terry is by far the best available. He's a professional and understands the process of NBA coaching and how to communicate and teach young players."
What is perhaps most interesting about this remark is not that it likely to be completely false, but that at the same time it might not be far from the truth.