Final answer:
No, the performance of a pre-existing contractual duty that is neither doubtful nor disputed does not qualify as consideration for a second contract because it lacks the element of exchange required for a new contract.
Step-by-step explanation:
The performance of a pre-existing contractual duty that is not doubtful or disputed is not considered legally sufficient consideration to support a second contract. This legal principle is based on the precept that a contract must involve an exchange of consideration that is something of value that was not previously required. By simply performing a duty one is already bound to perform, there is no new consideration, and therefore, no new contract can be formed based on that performance.