The Primal Ritual Shell is a proc trinket with an on-use effect to configure what proc effect it has. However, if you limit your on-use trinkets to 1 in gear preferences, it counts as an on-use trinket against the limit. This is unfortunate if your actual best trinkets in bags are equipping it alongside a real on-use trinket.
Another issue may be that the simulator might not understand what proc the trinket is configured to. The “default” proc is a mastery proc, but it can be set to do a heal, absorb shield, or fire damage proc.
Hey I know this is an old post but is the shell still set to mastery by default if it’s picked in the optimiser? If so it’s probably grossly undervalued for healers as the heal choice is near broken at the moment. Also just would like to know which to set it to when it selects it for my Brewmaster.