Thanks @Ragnarok101, found the notes.
First, good to know I’m not crazy, at least.
Second, I’m ok with the stated logic behind these changes, but the Law of Unintended Consequences is huge and ugly in this case: because their spread is tighter, gunners are now more dangerous at much further ranges, to the point that many builds (and Ogryn’s as a whole) are completely at their mercy. There’s not a lot of counter play – “where is that coming from? where is cover? too late I’m dead” – and overlaps too much with the sniper’s role. “Challenging” is fun, frustration is not.
In my first post I described gunners as a midrange threat. If that is in fact the intended role for these enemies, then there should be a maximum range limit on their targeting and engagement, i.e. make them close a little more distance before unloading.
Reduced engagement range would restrict the amount of space a gunner could effectively cover, in turn giving players a bit more of chance to see and react to the threat, while not affecting the danger presented by the bullet stream.