Necromancer Bloodstained Insignia question

The benefit of this insignia is to reduce casting time by 25% for spells related to exploiting corpses. Does non-stacking in this instance mean the benefit doesn't stack with other bloodstained insignias or with ANY other item/weapon which reduces casting time of these spells? Specifically - this character has a Ghial's staff. Should I not bother using the bloodstained insignia? Thx!

Bloodstained insignia will simply not stack with another bloodstained insignia - you'll only need 1 insignia of it. It will, however, stack with weapons that reduce casting times.

Only with other bloodstained insignas. If 20% casting time kicks in you'll still get the 25% from the insigna.

That's what I'd hoped to hear.
-Fuzzy