Something to play by ear and see what he thinks/how he reacts. It can be helpful at times but also hurt in the long run if the stutterer becomes more dependent on someone else speaking for him. Might vary by situation too. Speaking for myself, the example of giving a different name for dinner reservations is a harmless quality of life change. Ordering for him all the time at restaurants, in my opinion, veers into babying. As a stutterer, I find being exposed to stuttering the best way to keep it from becoming a problem. The more I hide, the more those exposures begin to hurt and scare me.