Negligence lawyers have long appreciated that the apparently procedural rules of limitation drive the substance of the law, because one can only understand when a cause of action accrues by analysing precisely what its essential elements are. Sometimes the substance is distorted in the process: we only worry about concurrent liability in tort and contract, and tort actions by clients against their advisers, because the limitation period for breach of contract accrues, and thus runs out, earlier than the negligence period. But occasionally, and paradoxically, limitation leads the courts into misunderstanding the elements of the cause of action, as happened, alas, in Daniels v. Thompson [2004] EWCA Civ 307.