Amen brother! I don't however think that these categories are therefore useless. We can group paintings and styles into groups in order to identify common problems or virtues that they may have without getting too bogged down by the individual cases that may benefit or suffer from them to a greater or lesser degree. Generalizations about styes and movements are useful for some things, but I agree that people sometimes get carried away with them and ignore what's in front of them because they are so in love with theory.
