So apparently, unless its a bug, you cannot mog 1 shoulder and hide the other. Either both are hidden or both visible. Each side can be different, but seems you cant hide just one shoulder
I can definitely hide just one shoulder on the 9.1 PTR. There are some bugs with mogging shoulders separately, though.
Ill have to try again. For me it was both or neither
Where r u guys testing that? in The Beta? or PTR?
PTR for this
10 Characters
So im on PTR again. I find i cannot hide just the right shoulder. I can hide just the left. Otherwise its both hidden or both visible. Can change either to whatever you want, but cant hide just the right shoulder