There's not been an accuracy value in Dragon Age games since DAO. You had a chance to miss or be resisted in the first game, on top of that you also had the Defense stat, which acted as a dodge function, and thankfully this died an early death. Reason being that it limited the useful gear to what ever gave the person the most likely chance to land their strikes -- which detracted from the gameplay.
In DA2, Attack functioned as a counter to the Defense stat solely, if the target has zero defense -- there's zero reason to have attack. Attack was still important, but there were ways to build around it, especially with stuns, sleeps, and other control effects -- If you couldn't act, you couldn't defend. That's if something lived long enough for it to matter -- Combos ignored defense entirely, as did Mages.
Now, Defense is a flat damage reduction on 3 categories, and Attack is an overall flat damage boost. However, thanks to plethora of on Crit effects, the importance of armor, and Defense, Critcal results are the more important method of damage dealing for all 3 classes. If however, you built around purposefully avoiding critical effects, then pure Attack is, yes, the best avenue for damage.
As for the topic at hand -- Attack is the lesser bad option here, take that.