Its the pilot. Poor equipment doesn't help but it is the pilot. A few years ago a friend won Masters at the nats with a plane that required bottom rudder in rolls!?! We affectionately refer to it now as the banana.
Now he is a top contender in FAI and will outfly most people with their airplane. Practiced with him a few weeks ago and a club member let him fly his plane. He immediately did a beautiful 4 roll oppisite rolling circle into a rolling harrier into a rolling loop then knife edge loop. The owner of the plane said he never would have believed his plane could do those things.
Watched Mike MCconville (sp) put in great flights at the Nats finals with his Ultimate and everyone knows the problems with bipes! ( tongue in cheek)
Let a Master finalist fly my plane the week before the nats and he flew my schedule better than I do on the first flight. Killed the excuses for a new plane right away.
Burn more fuel and go to more contests. Practice with objective feedback is the best way to improve. Of course talent helps.