It takes lots of nerve to sing a song associated with Elvis or Frank Sinatra or Sam Cooke. Maybe if you came with pipes like Aaron Neville you could get away with it. For most mortals it's really not a smart move, however.
Then you have Otis Redding. He was fearless and he could make anything his. Satisfaction, Down In The Valley, Shake. It never really mattered. Often he wouldn't even bother to check up on all the lyrics. I'm an eskimo and he sold me more than one refrigerator.
If you can still find a dictionary, look up soul singer. If there's not a picture of Otis, throw it across the room.