My wife has Lissa o’ the Bow as one of her followers and equips her with both daggers and a bow and Lissa will always use the bow at range but then switches to the daggers once the mobs move into melee range, so there’s obviously some choosing going on. I just wondered what they would do if they had two melee weapons that were roughly comparable but where one has more obvious application (e.g., the 1H Sword provides AOE coverage when being swarmed, whereas Telith’s provides more solid single target DPS).