Can leon Robinson the actor that plays david ruffin in the temptations movie sing?

In the movie, The Temptations, David Ruffin (played by Leon) is invited on stage by his brother to sing "Shout" with The Temptations. Leon is not actually singing but is lip syching to the voice of a talented saxophonist/singer by the name of Leonard Julien III. You can read more of Leonard Julien III at http://www.atlsound.com/TheBAND.asp?Page=LeonardJulien.htm

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