I massively highly strongly hugely doubt it’s an engine limitation. If it was regular, on-attack devotions would be impossible to bind to pets too.
There are multiple devotions I’d want to use on my pets. Of course, some procs would need to be restricted to players only (e.g. pet bonus ones, like Mog’s devotion right now).
Imagine Healing Rain Briarthorn or Light of Empyrion some other pet. Also, imagine Black Blood of Yugol bound to another pet, even thought it’d be a pet bound to a pet, but would look super nice.
Building pets using regular pet devotions is super coo… Uh, uhm, yeah, I will eat this hamburger! Uh, wait, what?
I’ve never made a pet build outside of the beta (back when Shaman was first released), so maybe I’m misunderstanding this. Are you saying you cannot bind on-hit devotions to pets and have them proc when the pets get hit? Can you bind attack devotions to pets to proc (Tainted Eruption) when the pet hits an enemy?