NEC: Is there really a difference between ‘approved’ and ‘accepted’?

Accepted and approved sound very similar. One is used in the NEC & the other is not. Is this just a matter of semantics or is there an important point of principle underlying this choice of words? What does it mean to “accept” under the NEC and are there any particular consequences ? Jon, Ian, Ewen and Rob discuss and come up with a simple suggestion to improve the contract.