From what my poor memory can recollect of the design document, archers have 2 modes of fire. One is volley (aka shoot a ton of arrows at a concentrated group and do damage to all or most of them, kinda like the archer model in Rome Total War), and the main one is the standard aim at a target and fire. Just like with all of our wacky and seemingly innovative ideas, we have to test these out in-game to see how much of an advantage, disadvantage, or nuisance they'll be, so we can't promise everything.