Even if the Wronglers were the worst band in the universe, I'd still want to go to their show this weekend, worm my way up front and give a standing ovation to every song simply because of the group's frontman, Warren Hellman. Hellman, as many may know, is the lovable billionaire who's made the Hardly Strictly Bluegrass Festival a reality in San Francisco for over a decade, at no charge whatsoever to the hundreds of thousands of fans who attend the world-famous event every year.

Luckily, the Wronglers aren't just decent, they're downright good. But don't try to tell that to Hellman.

"We rehearse twice a week," the dry, self-deprecating 76-year-old says on the phone from his San Francisco office, "and all the rest of the musicians have gotten really good. All but one. That's why I don't even introduce myself when we're playing."

Musing that there may be signs ("but not very many") that his banjo playing has improved slightly since the Wronglers first filled the opening slot at Hardly Strictly six years ago, Hellman predicts that 10 years from now, he "might be mediocre." It's the kind of overly humble assessment that the unfathomably successful investor is known for; he even keeps a low profile at his own festival, mostly because he's busy basking in the glow of performers he still considers idols.

An anecdote serves as the perfect example. "One of my partners was on a television show a couple weeks ago," Hellman says, "where it was he and Bill Gates and Warren Buffett. Somebody said, 'Does that make you jealous?' I said, 'No—but if he was on a show with Earl Scruggs and Doc Watson, that'd really piss me off!'"

In that light, the Wronglers is a dream come true for Hellman. At 28, as a young hotshot at Lehman Brothers, he once called Pete Seeger for banjo lessons and was sternly rebuked by Seeger's manager for being, in Hellman's words, "a plutocrat." He gave up the banjo for 30 years. It wasn't until he found support from his bluegrass heroes at Hardly Strictly that he picked it up again.

Hellman goes on. "I know this sounds too gushy or too starry-eyed, but I think the nicest collection of people I've met in my life are all these performers. I was in the nastiest, most competitive business that you could imagine for a lot of years."

That nasty business usually takes it pretty hard on the chin from the typical bluegrass fan, but the Wronglers' songs do occasionally call out white-collar criminals. One shows up in "O Isaias," an ode to Hellman's grandfather, who in the early century essentially financed California as we know it: "Henry Fleischmann was head teller of the Hellman bank / He was I.W.'s adviser of the very highest rank / Stole a million dollars, into debt he sank / Never was arrested, never thrown into the tank."

This weekend's Wronglers show is a benefit called "The Big Give Back," organized by local musician Arann Harris. To see Harris and his band live is like watching a rural preacher work a congregation like a plow works the field, although he's sadly been forced to lay low lately. In October, Harris was hit and seriously injured by a drunk driver on the way home from his family's farm, and the outpouring of support he received from the community while recuperating inspired his focus on the true reason for the season: giving. Thus, none of the show's proceeds are going to covering Harris' $8,000 in outstanding medical bills, but instead to COTS homeless shelter and kitchen in Petaluma.

Add in Scrooge as host, an ugly-Christmas-sweater contest, a raffle with gifts from local stores and a gang of special guests, and Hellman's looking forward to his first show in the North Bay.

"They said to us, 'This is a Christmas show, you oughta do a Christmas song,'" laughs Hellman. "Of course what they're expecting, I suppose, is 'Silent Night.' But we've written our own song. The opening line is 'Sweet baby Jesus, if only you knew / Just what your birth would lead us all to.' Do you think we'll be in trouble in Petaluma with that?"

Warren Hellman and the Wronglers with Arann Harris and the Farm Band play 'The Big Give Back' on Sunday, Dec. 12, at the Mystic Theatre. 21 Petaluma Blvd. N., Petaluma. 6:30pm. $10 with two cans of food; $15 otherwise. 707.762.3565.

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