I'm going to respectfully disagree here.
I have Myst on a few chars, one of them is a Mystic Dexxer.
When I cast Animated Weapon with my Dexxer (110 Tactics, 100 Anatomy) they weapon does the exact same damage to monsters as when I cast it with my Myst/Mage (0 Tactics, 0 Anatomy.... well... human so technically 20/20).
I'll retest this, but when I tried it before it was the same damage. Not worth the mana really.