Austin Considine, writing for The New York Times, has a story about how Metallica puts together setlists for their current tour. There’s a lot that goes into it. I love their idea of “Never again play the same set list twice.” But that doesn’t mean it’s easy to narrow things down. For that, they’ve come up with an elaborate algorithm:

Eventually, the band developed what Ulrich called a “slot” system based on the band’s different “food groups” of songs, a reference to their feel and tempo. Slot 1 (of 16) on the M72 tour, for example, will always be an upper-mid-tempo fan favorite — Day 1 at MetLife, it was “Creeping Death” — that has a quickly recognizable opening riff: not too fast or complicated. But the songs in that slot will rotate. Slot 10 should always be a ballad, like “Nothing Else Matters.” The closer is always “Master of Puppets” or “Enter Sandman.”

Ulrich also keeps careful data about what song the band has played where, and tries to tailor the set list accordingly.

“At times it turns into a science” he said. “We’re in Montreal now, and I’ll have all the info for the last 20 years that we’ve played Montreal in front of me. And I can put a set list together where the deeper cuts will not be repeated.”

I can’t even fathom a band like KISS doing something like this.