Casting the spell Manaflow doesn't disable other sources of Manaflow, such as a wizard hat of the arcanist - you can then evoke the talent from the item to get even more mana regen (if you have multiple arcanist-branded items you can swap to them and use them to continue increasing your mana regen).
However, if you use Manaflow from an item first, then the spell is disabled and cannot be cast.
I don't know whether you're supposed to be able to stack multiple sources of Manaflow at all, but if so then it should work either way round, regardless of whether you cast it as a spell or evoke it from an item first.
[b35] Manaflow from spells and items is inconsistent
Moderator: Moderator
Re: [b35] Manaflow from spells and items is inconsistent
They shouldn't stack. I'm guessing items aren't checking the talent pre-use code.