Four hours or so before they’re due beneath the massive wraparound video screen at Sphere, Bob Weir, Mickey Hart and John Mayer amble into a backstage production office like three guys showing up — again — for the work of blowing 17,000 minds. “Nice to meet you,” Mayer says, grinning as he extends a hand. “John Mayer, Mayer Industries.
” As original members of the Grateful Dead, guitarist Weir, 76, and percussionist Hart, 80, are jam-band royalty; Mayer, 46, is the singer and guitarist known for pop hits like “Gravity” and “Your Body Is a Wonderland.” Together they represent the nucleus of Dead & Company, which on this recent afternoon has just passed the halfway mark of a 30-date summer residency at Sphere, the state-of-the-art dome-shaped venue behind the Venetian resort on the Las Vegas Strip. Not that they’re counting.
“Halfway? If you say so,” Weir says as he lowers himself into the lotus position on a sofa next to his bandmates. Adds Hart, his hands encased in his trademark white golf gloves: “This is just a habit for us. We keep coming back here three days a week and playing our stuff.
” A year ago, they seemed poised to shake that habit: Having logged more than 200 gigs since 2015 — when the band came together in the wake of a public farewell by the Grateful Dead — Dead & Company wrapped up what was billed as its own final tour that July with three concerts at Oracle Park in San Francisco, where the Grateful Dead formed in the mid-196.