Today I was studying a Mozart piano concerto in the light of the orchestral voicing, particularly the French horn part. I came across a most unlikely harmony in which the horns, playing in octaves, play the tonic tone, which throws the whole exotic harmony out of balance. In all the performances of this piece I have ever heard that imbalance was never allowed to dominate the moment. If I were to conduct you may be sure it would!

Such things are always a matter of personal taste. But taste has to be backed up with a sense of the composer's skill in writing down exactly what he had in mind, whether or not it meets contemporary standards of good taste.