In Barclays Trust & others v Ernst & Young LLP (2016) the court dismissed what it described as an opportunistic claim for negligent misstat

In Barclays Trust & others v Ernst & Young LLP (2016) the court dismissed what it described as an opportunistic claim for negligent misstatement against professionals based on an immaterial breach of duty and framed with the benefit of hindsight. With reference to case law, explain how the courts determine whether such claims for negligent misstatement are valid, and where they have dismissed such claims.