Boston’s teaching hospitals have been so widely praised for saving dozens of Marathon bombing victims that trauma surgeons worry the state will grow complacent. They met with legislators Tuesday to remind them that luck and timing played a role on Patriot’s Day, and that the trauma system still has gaps that require attention. Frederick Millham, HMS associate clinical professor of surgery, and George Velmahos, the John Francis Burke Professor of Surgery, both of Massachusetts General Hospital, are quoted.