I would say if a certain percentage (or fractional percentage) of the general population has a "processing" advantage, and they are equally represented among tr

I would say if a certain percentage (or fractional percentage) of the general population has a "processing" advantage, and they are equally represented among trained musicians, then the more accurate your measurement techniques, the more conclusively they would find no difference. This should be tried among those who have no training and are prodigies or equivalent. Also repeated among those who pull their weight on the same "instruments" more through instrument familiarity rather than pure musicianship.