How common is it for models in AOS to ignore/re-roll battleshock? I can see some combos that would reduce enemy bravery by three or four - but I know that in 40k that's not terribly useful since re-rolling leadership is standard on half the armies, and the rest can usually drop a hat to ignore it. Is that the case in AOS? I know there'll be a command ability to re-roll that anyone has access to, but that has to be used at the start of the enemy's turn (so if I'm lucky, I can get a turn without it) and costs a command point that they can't then spend on their favourite ability.