Everybody does their maneuvers big. It may be the judges that need calibrating. Get confident with your maneuvers, and then use that as a basis for arguing with the judges!
There are definitely people who *do* routinely fly undersize, although they are in the minority. Usually their figures tend to be unrecognizable, and it is *very common* to coach people to fly larger in order to better manage the shapes, bottoms, precision. When people start to learn to fly square maneuvers, they typically make them *much smaller* than they should be or can be.
Or, they fly a lot by themselves, and can't tell the difference without resorting to mechanical measurements. I know this because *that's exactly how I started*, I flew day after day after day, nearly every day for several years, with angle and height markers to indicate 5 feet and 45 degrees, and at times, 5 foot radius markers. I was nailing the 45 degrees and at least attempted to nail the 5 foot radius. The first time I flew with other experienced modelers, Dan Lutz (one of the local fliers in Lexington, KY) ran out of the pits and screamed at me *MUCH BIGGER*! Because while I was hitting the 45 like a laser beam, my airplane and engine were in no way up to the task, the shapes were unrecognizable, and I would get a better score if I opened up the maneuvers and gave up size accuracy for superior shape and precision accuracy.
I have told people to fly larger on many occasions, because while they might be flying the right size or even too small, they are committing many more serious errors in the effort and may be beyond the capabilities of their airplane, and their score would be greatly improved by flying bigger but more accurate and precise shapes.
And in any case, no matter what the comment or advice, the judges have usually seen thousands or tens of thousands of flights from all sorts of skill levels, and are in perfect position with perfect perspective to see what might improve the pilot's score, because they just got done figuring out what errors the pilot committed.
The point of stunt competition is *not* to more accurately execute maneuvers - it's to make the judges think you are more accurately executing the maneuvers. Advice like that, or even just the posted results, are *always,* repeat, *always* critical input. It's really the only evaluation that matters, far from arguing about it, it is telling you *exactly* what you need to know. Take advantage of it!
Brett