I have been saying this has been in place all along. I have been a NCAA Division I Baseball umpire for 25 years, and you would be surprised by the amount of crossover there is with officials from other sports. I personally know guys who have been NFL officials, as well as a couple who are currently. The evaluation policy of the NFL is extensive. There are seven officials on the field for every game. Each and every one of them are "graded" on every single play, regardless if they make a call or not. Positioning and mechanics are as big a part of the evaluation as judgement.
As someone who has also served as a Supervisor of Umpires for a Professional Minor League, this sort of program is common. As Blandino explained, each official is ranked and those who tend to fall into the bottom tier, are put on notice. Show improvement or your days are numbered. This has been the case for years, it just isn't ordinarily made public. That Blandino felt inclined to even discuss this, tells me that the league felt the need to do a little damage control. They just survived a work stoppage a couple of years ago, combined with all the emphasis being put on safety, which leads to much more "judgement" based interpretations from the officials, the NFL has a PR problem as it pertains to officiating and this is their attempt to address it.