One may be the loneliest number. But sometimes it’s the only number you’ve got. Over and over again. That was the case on Monday, as a trio of superstar singer-songwriters dominated the Late-Night TV Music proceedings. John Legend got Wild (but not really) on Late Night With Seth Meyers; Sam Smith brought out Diamonds (but not really) on The Late Late Show With James Corden; and Nathaniel Rateliff assured us And It’s Still Alright (and it was) on Jimmy Kimmel Live. Enjoy.