There are five basic components of correct singing. Those are pitch, breathing, rhythm, diction and voice.
Bert , has all those qualities, this is not anything to do with taste, his diction is good it is perfectly clear what he is singing about, his breathing is good his rhythm is good and his voice is clear. furthermore his interpreation of narrative ballads is such that he sings the story.
    I received this message from A MEMBER that he was a horrible singer but a good scholar, this person is in reality saying he is not to my taste., NOT the same thing at all
However as part of a sensible criticism this sort of vacuous remark misses the point of the discussion.
1.singers can be good singers because they have the basic components of correct singing and perhaps not be to everybodys taste, however in BERTS CASE HE HAS MORE THAN THAT BECAUSE HE HAS THE ABILTY TO INTERPRET AS STORIES THE NARRATIVE BALLDS,that is not just an opinion it is a fact
good singing is not just about taste, Roy Orbison was a good singer, but not al lof his songs were to my taste some were, some were not, that does not alter the fact he was a good singer
DISCUSSING A SINGERS ABILTY IS NOT JUST ABOUT TASTE
   To make a remark that his tone is not to my taste is a sensible remark, but an opinion, his tone does not make him a bad singer, or a horrible singer, there are as I have remarked other components that determine good singing