Having duets at the American Country Music Awards was great in theory, and rough in execution. Steven Tyler and Carrie Underwood were the only two artists to get it right. Tyler entered the stage singing Underwood’s Undo It, and Carrie Underwood later sang Tyler’s Walk This Way. This idea of artists crossing genres should have been consistent with each duet, but the producers missed the mark. Instead, you had Rihanna singing California King Bed with Sugarland‘s Jennifer Nettles, but Jennifer Nettles didn’t sing a song by Rihanna. To further confuse the theme, Brad Paisley sang with Alabama, who are being labeled in the press as “rockers,” even though they are both clearly country music artists. That’s not exactly crossing genres. The ACM producers should call American Idol producer Nigel Lythgoe to take some advice about executing performance themes. Watch Underwood and Tyler below.