lets not get ridiculous and start another war here, anyone who has ever flown competition in the modern age will tell you knife edge mix correction is not cheating. It's a competitive advantage to fully utilize the programming features of your computer radio to correct for a given airframes aerobatic shortcomings. During the Freestyle portion of an IMAC contest, should we not mix spoileron to stop wing rock in harriers and elevators? If you think using a mix somehow shows that you don't have the skill or coordination to fly a maneuver properly, by all means show up at the TOC or F3A world championships and share your views with any flyer there and see what their reaction is. To build on what Minnflyer said, your knife edge mix may have been set up on a day where air density and wind direction may have been different due to weather and temperature changes, so you show up at the contest to totally different conditions, the guys at the top of the leader board are using their brains and slightly correcting to keep their headings spot on. The mix will at the very least get the airplane in the ballpark. Cause you know what, the guy in the pit next to you is doing the same thing, and who wants to show up with one strike already against them? "Precision Aerobatics" takes more then a mix to do properly.
Bottom line, if you don't think using a mix is flying, don't use them, the other guy with arrow straight point rolls and KE loops will be glad to let you hold his 1st place trophy! HAHA!