The question in the title: How to ask for a dose change without antagonising anyone I will give what I have already checked below so nobody repeats it.
Asking about a population rather than about a person.
The published trials in this class mostly enrolled a fairly specific group, and the questions here frequently come from people well outside it. I would like to understand what the honest position is when someone falls outside the studied population: not "it is fine" and not "there is no data", but what the reasoning actually looks like.