IIRC, the 85L is focus-by-wire [i.e., the focus ring is not mechanically coupled to the focus mechanism] which makes the MF a bit less tactile. And there are some awfully big heavy elements in that there lens for the focus motors to be shoving around.
All good technical reasons, to my mind, why the focusing performance of the lens feels a bit "off" to those used to more modest lenses that don't have either of these issues.
I would also say that you probably want to put in some hands-on time to offset review reading. There is the unfortunate tendency in these digital days for some shooters to
obsess about tiny technical issues that may not actually affect you practically in shooting as much as they say it will.