Did you try at all explaining to him that technical proficiency is essentially antithetical to most forms of Metal and that the amateurish performance tends to be half of the charm of the music in its efforts to thwart the traditionally held notions of what is acceptable music? That's the only way that I can possibly see him finding any appreciation whatsoever with 'traditional' singing in Metal. By the way, his response reads a lot like I would expect a response from my philosophy professor, whose expertise is in aesthetics, primarily the study of the aesthetics of classical music. You know, except without the slight dogmatic undertones. I didn't mean to come off as a bit obtuse before regarding his response, and if I did I'm sorry for that. I think it's really cool that he would actually put any marginal amount of effort into attempting to understand this music, regardless of how short I feel he's fallen from 'getting it'.