Every film I've ever worked on, and that includes 'Braveheart' and 'Trainspotting,' I've always witnessed a director having a breakdown. Every director will have a day, without exception, where they just can't do it anymore, they don't know what to say to their cameraman, their cast. It's the sign of real, physical exhaustion.
For us as writers, it's really important to have songs we believe in - even before sometimes we shoot a scene. If we have a song that's so perfectly designed for a scene on 'Rescue Me,' we'll play it on loud speakers during the shooting. It helps the cameraman and it helps the director, and it helps the actors know what the feel is.