on a directional board the tip will be longer than the tail(measured from the inserts). there is usually a slight setback on the inserts and the sidecut. they can be ridden switch and if you aren't having issues with it then i wouldn't worry about it.
well i was wondering if it would make a difference manualing, because i can much easier ride the nose in a mannual then the tail. and also, i usually do nollies, because of the same concept and get more air.