A delegation will be null and void if it poses any threat to the commercially reasonable expectations of the obligee.
Unlike an assignment, a delegation is virtually always for consideration, and never donative - few people are going to accept the charitable offer to perform a task contracted to someone else.
A parallel concept to delegation is assignment, which occurs when one party transfers his present rights to receive the benefits accruing to the assignor under that contract.
Another common law rule requires that a party to a contract can not delegate performance that involves special skills or reputation (although it is possible to have a novation under such circumstances).
[7] However, there are many times when delegating law-making authority to an agency is appropriate, especially when the legislature lacks the capacity or expertise to handle a randomly evolving issue that affects multiple jurisdictions [7]