Well let me just give you a list of "common beliefs" that I have found wrong in the last year alone:1) THD and IMD indicate perceived distortion - wrong! In a widely quoted subjective test we showed that there is no correlation between THD or IMD and the perception of distortion in an audio system.
2) Compression drivers have too much distortion for quality sound - wrong! In a recent, as yet unpublished, psychoacoustics study of compression drivers no one, out of 45 subjects, could detect any level of nonlinear distortion in any of three different makes of compression drivers - all the way up to the thermal limit of these high end pro units. There is NO perceptable nonlinear distortion in a compression driver - none!
3) Horns and compression drivers cannot be made with "audiophile" caliber sound quality because of their distortion - wrong! In a double blind subjective study of my designs using a waveguide and a compression driver, 15 subjects rated this system equal to or better than a high end "audiophile" system using audiophile "Danish" components. (And costing $4500 each I might add!)
I have long held the belief that small rooms should be very live - completely contrary to popular opinions. I point my speakers in board - I don't listen on-axis.
Basically, I have come to at least question every "common knowledge" aspect of audio until it has been proven through statistically significant double blind psychoacoustic tests. So I may not disagree with everything but I accept nothing based on "experince", measurements, etc. If it ain't been proven in a valid double blind test it ain't necessarily so.