Well, I'd like to see the rule allowing me to have a taller tail section, too -- after seeing some photos Pork Pie took of me at speed, I can see how there must be a big burble following me down the course. Another 6" of height in the tail section would be enough to allow the bike and my butt to present a clean angle to the air. It'd be interesting to experiment, at least -- don't know if it'd make much difference.
ECTA allows Scott Guthrie (and others, I suppose) to have a much taller rear section -- I wonder if he's quantified the changes this higher back end brings about.