“singer who defied musical categories…”
but “musical categories” are of course only defined with hindsight, not in advance: a more accurate (or do i mean helpfully argumentative?) description might be “singer who refused to kowtow to the routine distillation – which is to say enfeeblement – effected by latterday niche-marketing and/or (same thing) critical credulity”: refinement entails a loss of power bcz it entails a loss of [scientific-semantic truism alert] potential