Once we have accepted the order from the customer based on our capabilities and abilities then there is no question of deviation and we must ensure that the job is exactly done same way as desired by the customer. Once the job is successfully completed then it can be delivered to the customer along with the documentary evidences. There is absolutely no problem doing that.
Knowledge is power.
But if you have to do some research and develop a product we can't make a document for the methodology you have to follow. One has to try various methods available and finalise the best way to do it. After finalising the process only one should make a document and hand over the same to quality department and production department so that they will follow the document strictly without any deviation.