Robinson was employed as an assistant manager in Gallagher Drug Company Store. He was accused of theft and embezzlement, which he admitted to, and was fired. The following day, at company headquarters, he signed a contract promising to repay the company $2,000. Robinson made payments totaling $741, and then stopped. Gallagher sued for the balance. Robinson's defense was that he had signed the agreement under duress. What logical problem arises in Robinson's arguing that he became aware of the duress after he attended a support group for unemployed managers?