Keep in mind that the theoretical work in machine learning tends to come from a rather different academic sphere from a lot of work in application. That means a

Keep in mind that the theoretical work in machine learning tends to come from a rather different academic sphere from a lot of work in application. That means a different professional vernacular, different notational conventions, and different ways of expressing certain concepts. I don't think it's quite reasonable to fault an academic for writing under the conventions of their field. That's not being needlessly obtuse, that's being as clear as possible for the intended audience. There's no call for sour grapes just because you happen to not be the intended audience of an academic paper in a field you don't actively participate in.