Drawing on advanced statistical modeling techniques (and the analytical wizardry of RPM developer Jeremias Engelmann, formerly of the Phoenix Suns), the metric isolates the unique plus-minus impact of each NBA player by adjusting for the effects of each teammate, opposing player and coach.
The RPM model sifts through more than 230,000 possessions each NBA season to tease apart the "real" plus-minus effects attributable to each player, employing techniques similar to those used by scientific researchers when they need to model the effects of numerous variables at the same time.
RPM estimates how many points each player adds or subtracts, on average, to his team's net scoring margin for each 100 possessions played. The RPM model also yields separate ratings for the player's impact on both ends of the court: offensive RPM (ORPM) and defensive RPM (DRPM).
based on this description, this was months if not years in the making. Like any advanced statistical modelling, the proof will be in how well it matches reality. Of course, unlike most phenomenons, the one modelled by this can't really do that. With weather and economy and even global warming, all you have to do is wait and see how it goes. Since there will never be any way to rank nba players with certainty, I guess people will love or hate this model based on how much it matches their own perception.
Which is why I said many raptor fans will hate it ...