In Hennigsen, the court concluded, after a detailed discussion of statutes and cases, that it was unfair to allow an automobile manufacturer to escape liability for personal injury from defective parts merely by including the warranty provision in question in a standard form, take-or-leave-it contract.
In Gatton, the court concluded that the waiver of the right to participate in class actions was unfair because, in the circumstances, a class action was the only viable form of litigation dissatisfied customers would have against T-Mobile. The provision in effect took away the right of judicial redress.
It is difficult to give any general guidance as to questions about substantive unfairness. Each situation must be considered on its own merits.