The documentary mini-series, slotted neatly into the quarter-hour gap between the end of the World at One and The Archers, has become a staple of the Radio 4 afternoon schedules. It is also a prime example of the expanding suitcase theory of broadcasting, which holds that absolutely anything, from the American War of Independence to the origins of Western philosophy, can be crammed into a series of 15-minute instalments if you go about it in the right way.So how do you satisfactorily contain so sprawling a topic as the history of military deception in five brief episodes (26-30 October)? Ben Macintyre’s guide was the ancient Chinese theorist Sun Tzu, the fount of all manner of paradoxical epigrams about the best time for a show of strength being when your forces were seriously deple