A coupe of days ago Totalbiscuit interviewed Gabe Amantangelo, and in this interview he clearly explains why Ops were nerfed.
"OP's were scored too high relative to the other classes". It was a design error and now they are fixing it.
Video Link:
LISTEN CLOSELY FROM 10:00 to 11:30!
Starting at 10:38 -"We do a ablitiy scoring system and a overall class scoring system"
10:47 - "With the volume of stuff, leading up to launch SOME OF THE ABILITIES WEREN'T SCORED EXACTLY CORRECTLY, or some of the data was missed, so we are fixing some of those things"
11:00 - "AND THIS CHANGE ACTUALLY INVOLVES THAT, IT WAS SCORED TOO HIGH RELATIVE TO THE MEAN OF THE DIFFERENT CLASSES"
Operatives were OP from the beginning. This PROVES it.