I have also wondered this. I think the eggheads probably as between them they have more obscure knowledge especially in arts, sculpture, literature (the heavy stuff) whereas the chasers are better at a wide range of quickfire stuff. Just an opinion.
Well, the 2011 European Quizzing Championships were held in Bruges at the weekend, and here's how how the Eggheads and Chasers were placed in the individuals:
1 Kevin ASHMAN
2 Pat GIBSON
31 Paul SINHA
41 Anne HEGERTY
71 Barry SIMMONS