This is about as unprofessional as it gets. The gaffer should voice his opinion about the lighting - he was hired to provide that expertise. To remain silent is a disservice to the job. If the director insists on lighting a certain way the gaffer should comply with his request, however that doesn't mean he should shut up. From what I've read Chagrin conducted himself in a professional manner.you asked if you should just shutup and screw up the shadows and nice lighting setup you made. the answer is yes, it's his film to screw up if he wants to.
Pulling the director aside avoided a potentially embarassing situation. Chagrin voiced his objection. The conduct of the director in unfair and uncalled for. There's no reason to start playing the blame game - it serves no purpose and does nothing to move the film forward.We took a little walk to another room and I explained what bouncing one of his beloved photofloods would do to the scene.
Even though the director is seemingly incompetent we shouldn't allow the actions of others to dictate how we behave. Meaning, it doesn't matter if the director is an idiot, a jerk or a genius. Chagrin should conduct himself in a professional manner. IMHO posting an ongoing diary of the experience crosses the line of professional behavior.
my 2