Oh that thread gets better the more replies you read:
Original post:
"So if they both muster knights and archers in their respective dukedoms then advance at similar speeds, the battle will take place somewhere on the northern fringe of London, maybe in car park at the Waltham Cross Homebase"
Some replies:
"Sussex would have to move his forces up (and over) the Downs so will be slower. He's not the Grand old Duke of York (who would be on the Cambridge side, of course, advancing from Pizza Hut, Woking)"
"You're right that would slow them down. A fast advance of Cambridge forces down M11, then round the M25, would mean they can reach Sussex borders early and maraud the countryside, burning barns, orchards etc so the Sussex army would starve in winter."
"I think you forget the financial penalty that would incur the Cambridge forces using the Dartford toll bridge. They may be forced to detour through London using the Blackwall tunnel, where they could be congested for days."
"By laying fragile dog bowls across the battlefield, cambridge will render it impassable to the forces of sussex"
And:
"Would a trebuchet be subject to a congestion charge, the website isn't clear on the matter"