I could have sworn in the past I use trebuchets to kill a garrison before a siege.... but trying it just now they don't do anything unless there is a siege weapon in the castle for them to shoot at and they didn't kill any enemies when breaking the walls, they just site there afterwards. I also tried fire ballistas and the same thing. AM I missing something or did I get a Mandela effect from last month in an alternate world were siege weapons were useful?