AUSTIN, Tx—In the summer of 1993, I spent several days in Seattle waiting to be summoned for an audience with Kurt Cobain and enjoying quite a bit of quality hang time with Krist Novoselic as they waited for the release of Nirvana’s third album In Utero. As a drummer myself and a fan of Dave Grohl’s postpunk John Bonham thrash, I repeatedly asked both of his band mates, “Shouldn’t I speak to him, too?”

“Heck, no; why?,” came the reply, and more than once. So I settled for watching Grohl play a reunion gig with the D.C. hardcore band Scream at the Crocodile Café.

Two years later, when I queried Courtney Love on her perception of Grohl’s role in her husband’s band, she burst into that infamous evil cackle. “What you have to know about Dave is he was the guy who’d enjoy going out back to set his farts on fire with Steve Albini. That’s Dave.”

I relate these anecdotes with no sense of malice but in the spirit of the engaging, heartfelt and often very funny string of historical reminiscences with which Grohl traced his career from D.C. punk to alt-rock superstar to Foo-Fighting superstar while delivering the keynote address Thursday morning at South by Southwest, all building to the always-welcome conference fail-safe messages of do-it-yourself  independence, “the musician comes first” and “find your own voice.”

Grohl entertained by scat-singing Edgar Winter’s instrumental “Frankenstein,” a childhood favorite that introduced him to the world of rock, and by demonstrating how he’d use two clunky cassette recorders to improvise his own multi-tracked recordings as a young teen.

Much of the written-out speech—delivered from behind a pair of reading glasses Grohl claimed to have purchased at the drug store—centered on his epiphany in Chicago during the family’s summer vacation in 1982. His older cousin Tracy had become a punk-rocker, and she introduced him to her endless stacks of snarling 45s. He soon discovered the Wax Trax record store, he saw Naked Raygun play at Cubby Bear and his course in life was set.

“I wanted to be someone’s Edgar Winter,” the musician said. “I wanted to be someone’s Naked Raygun.”

Miracle of miracles, his accomplishments exceeded both. The tale of how Nevermind, a record everyone expected to sell 35,000 copies in its first six months (if they were lucky) soon was selling 300,000 a week and “forever changing the music world” now is rock mythology. And Grohl offered no more insight into how that happened than Cobain or Novoselic did: “Maybe it was timing… Maybe it was a generation of kids sick of Wilson Phillips.”

Then came the Foo Fighters, a band one could legitimately champion on its first album, a cathartic garage-rock record that Grohl recorded on his own “as therapy,” just like those teen experiments with multi-tracking. But from there, it promptly became an example of the worst sort of pandering modern-rock band unleashed by the alternative era, one that would play any corporate-rock radio festival, one that essentially beat the same tired song into submission over and over again through a seven-album discography, and one that has less in common these days with Nirvana than it does with Rick Springfield (a hero inexplicably lauded in Grohl’s Sound City documentary, as if the man behind “Jessie’s Girl” is equal to greats such as Neil Young, Tom Petty and Dr. John, who also recorded at that now-celebrated studio).

Who is the real Dave Grohl—the one of those anecdotes at the top of this post, or the one who spoke so movingly at SXSW? I don’t know, and I’m not sure it matters. Authenticity, after all, is a fake construct, and the most soulful sounds at SXSW or anywhere else are always in part show business. In any event, Grohl gave a heck of a keynote—every bit as good as the one last year by Bruce Springsteen, with whom he told us he recently dined in preparation for his big moment at the podium.

My complete coverage of SXSW 2013

Laura Stevenson, Holydrug Couple, Foxygen and more

Imaging, jingle-crafting, crowdfunding and ‘Born in Chicago’