It would take a lot more than 15 months to finish drafting the constitution if debating and educating people are included in the process, as Burin Kantabutra suggested.
We should bear in mind that no constitution is perfect. A charter is a group of words that forms a country’s rules of law. They are impermanent by nature, and need adjustment and change over time.
Hence, a referendum should be held as a check on the charter drafters’ job in writing the charter to ensure that glaring errors do not happen.
That should be the duty of a referendum.
Vint Chavala
Bangkok