Back in the good old days of six or seven legs a day up and down the east coast with no dispatcher and no flight attendant(s) but still trying to make fifteen minute turns, I tried to set the tone by briefing the first officers that "I have one speed: I don't rush and I don't waste time. If you need a Coke, go and get one. If you need a pee, go and pee. If you see someone you know along the way, say hi and keep going."
Since those days, I have seen fireflybob's raised palm used effectively, as long as it conveys the sense that "you are in the queue" and not one of irritation.
Recently, however, I watched a captain handle one of these situations very well. It seems that operations had generated the general decs a day earlier (no doubt using advanced multi-tasking techniques), and consequently they had failed to capture two changes to the crew roster. Naturally, as we neared departure time and discovered the error, ops wanted the captain to use his authority to overwrite the names and sign off the general decs (all fifteen copies). He politely explained that he would do so but not until the cockpit crew had completed all of their preflight tasks, including checklists, etc. Not only did this preserve the cadence of the cockpit preparation, it also established a planned queue for the necessary tasks. This planned queue was front-loaded to allow time for other, as-yet-undiscovered-but-possibly-more-serious issues to be managed. Everyone's attention stayed focused and on the same page, and everyone knew what was next. It was CRM very well executed.
Of course, it had the accidental byproduct of placing credit for the inevitable delay squarely where it belonged. Oh well...you can't cover everything...
