Question: Who sings i can't tell you why by the eagles?
Disambiguated questions and answers: question: Who sings lead vocals on i can't tell you why by the eagles?
Who sings counterpoint on i can't tell you why by the eagles?
answer: Timothy Bruce Schmit
Timothy B. Schmit
Schmit
Frey and Henley
Glenn Frey and Don Henley
Natural Questions answer: Frey and Henley singing counterpoint
Schmit (from the Wikipedia article "I Can't Tell You Why")