Andreas Scholl, the countertenor, made a record of folk songs and I thought it was bloody awful (do note "I thought...") Can he sing? Of course he can sing. Kathleen Ferrier sang folk songs to Britten's piano arrangements. It sounded lovely but it doesn't do it for me at all as "folk music" (I keep it in my stash of classical music). Could she sing? You bet!

How you respond to a performance of a song (apart from said response being incredibly subjective) is very complicated and it unconsciously takes into account all manner of stuff such as genre, the words, gender of the singer, nationality of the song as well as the singer, complexity of the arrangement, your own previous listening experiences and preferences, your mood at the time, the company you're in and probably about 20 other factors. To say that such-and-such is a crap singer, or whatever, marks one out as a total prat, not worth conversing with. I think Bob Dylan's a crap singer. But dig deeper and you'll find that I also don't care for most of his songs, obscurantist lyrics don't do it for me at all, I dislike his harmonica playing, he's sold his soul to the commercial devil, he ripped off Nic Jones (IMO), he's a bit rude, etc. etc. So, very subjective stuff, this. There is no one way of singing well. One man's fish is another man's poisson. In many ways, hardly worth talking about!

(So I'll probably shut up...)