...and I'm pretty sure that a BFG (Big F*cking German) Con would be a great success - IF
(a) it'd be placed somewhere in the Rhine-Rhur area (highest population density, 2 major international airports, dozens of universities, close to the Benelux states, quick&easy to reach from Paris or London, etc.) - Düsseldorf would probably be best (they are used to the German "Karneval" and the "Altstadt" near the Rhine would be a great place for some serious partying...)
(b) it'd be scheduled between the latter half of July and the first week of August - summer holiday at schools and universities + good weather