#1 - Dec. 7, 2016, 11:37 p.m.
For more clarity on why: we're getting to the point of the PTR development cycle where we're starting to make heavy changes intended for overall performance balance between classes. In the past, this would have been done by changing each affected spell individually, which can be a slow process. To allow for more rapid iteration during the PTR process, we're instead those putting changes into a passive aura for each spec. That means only 1 "spell" needs to be modified, instead of several, which allows us to make more adjustments in total per build.
Once the PTR cycle is concluded, these adjustments will most likely be moved from that passive aura into the baseline spells, but in the meantime, please be aware that what's seen via datamining may not immediately show all of the actual changes that have taken place.