If the "Air Boss" is talking continuously for 20 minutes then there is something VERY wrong with the plan! The plan should be such that there is little, if any, talking needed to coordinate, and that plan should be sufficiently well briefed and "walked through" to ensure everyone understands their part in it. If the successful completion of any display item requires that amount of talking then it is a bad plan.
I am also concerned, from a UK perspective, why there were 5 people on the B17? UK rules dictate that only the minimum operating crew should be aboard during any display flying. I would expect that to be 2, or at the most 3?