Well from what I hear around the Clubs including my own, I think some already do! A lot of people who are described as Tone deaf or describe themselves as so, can often be thought to sing quite tell or to some standard. But if they're literally tone deaf then I'd say no and I count my own Brother and my Brother in law as two who truly should only use their voices for talking. there's some quite good singing exerises on line and vocal exercises etc, for anyone wishing to try