I suppose it's neither. It's something that was an artifact of how we implemented miasmas. We looked into the implications before we released the revamp out to testlive, and we did not discover any substantial advantage to not use daggers with the miasmas. This being the case, we felt there was no particular reason to add a dagger requirement.
Thanks for the explanation, Ilaliya.
It does, however, look hilarious with a crossbow in hand.
Oh okay, I had never seen multiple mitigates for the same hit. Thought it was possibly a combo bug. Carry on
All mulit-hit combos are afflicted with this bug. The dirty little secret is that mage shields actually were mitigating far more than intended on most dual wield combos (sin, reaver barb, and carnage conq were most affected) when 1.5 went live. I remember seeing a bloodbath combo loosing more than 450 damage to a mage shield when I tested it about a year ago. Since then it has been fixed and mage shields only mitigate 92 damage per combo finisher for all combos, but the combat log still shows the bugged mitigation (and actually shows as absorbing and mitigating 92 damage per combo hit).