According to my understanding, there is a clear provision of precedence of document in other standard form of contracts, such as JCT and FIDIC contract. However, it seems that relevant provision is intentionally omitted by the contract drafter of NEC contracts. If there is ambiguity or inconsistency, the only way out is to ask the Project Manager to step in under Clause 17.1.
So the question is: will it create uncertainties for the parties as they will never know how a document will be interpreted during the tendering stage?
Also, I would also like to know the reason behind such arrangement. Why don't the contract simply say something regarding precedence of document? Thank you.
Last but not least, as a Project Manager, how can I access and instruct in accordance with Clause 17.1 so as to protect the parties' interest and prevent my judgement from being challenged by subsequent adjudication / arbitration / litigation? Is there any rule of thumbs or guidelines I should follow? (Say, contra preferentem rule?)