In general, what is really needed is to identify the central theme of the question in front of you, to determine how much to write on a particular issue.
When discussing the duty of care for negligence in cases of special relationships (doctor/patient, manufacturer/customer etc), is it necessary to still talk through the Caparo test etc or is it sufficient to state that this is an established duty situation, e.g. (Donoghue v Stephenson) for manufacturer/customer.
If it is about duty of care, then you will need to discuss the general principle, its application and various control devices to impose or deny a duty of care. However, a question may slant towards either Standard of Care or Causation, the issue of duty of care may be dismissed in no more than a paragraph why duty of care has arisen but you must before moving on. There should be a mark or two awarded here.
At all times, you need to pay particular attention to policy reasoning when applying the judge-made laws.