The Limits of Wargaming #2: Betrayals, Surprises and Strategic Advantage

10th July 1460, near Northampton, England. Battle of Northampton. It’s the Wars of the Roses. King Henry VI — well His Grace’s advisers, anyway — the Lancastrians, if you must — versus the Yorkists led in this case by the Earl of Warwick .
The King’s forces have fortified themselves into a bend in the river.
They’ve got a ditch, wooden stakes, perhaps carts, certainly cannon. They’re gearing up for a rerun of the Battle of Castillon (an English defeat so utterly embarrassing that the swords of fallen English men-at-arms are a scholarly category in their own right!)
Warwick’s men advance into a hail of armour-piercing arrows, cannon balls and crossbow bolts. It looks as if he’s going to try to grind through the defences — the battle will be down to killing power and morale.
Except it doesn’t turn out that way.