Jan. 30, 2015. Seattle, Washington.

Music from two of the grunge era's greatest one shot bands fills Benaroya Hall, some of the songs blanketed with 20 years of dust. But there they were: members of Mad Season and Temple of the Dog, backed by the Seattle Symphony Orchestra and featuring guest bassist Duff McKagan.

McKagan was filling in for original Mad Season bassist John Baker Saunders, who passed away in 1999, and Chris Cornell took the microphone for Layne Staley, now gone a dozen years. Eddie Vedder aside, the Temple of the Dog lineup was complete.

Reviews of the show have been remarkably good, with Rolling Stone noting that "what could have been little more than another rock reformation gig turned out to be a genuinely special, surprising show that both exceeded its own hype and outdid its own billing." Dozens of cellphone videos of the show popped up on YouTube almost immediately, their comments sections overflowing with praise.

While that gig was going on, I was seated on my couch, watching Showtime's 'Quiet Riot: Well Now You're Here, There's No Way Back.' Quiet Riot were one of the first hair metal bands to break nationally, racking up millions of record sales on the backs of hits like '(Bang Your Head) Metal Health' and their cover of Slade's 'Cum on Feel the Noize.'

As in the case of Mad Season, a full Quiet Riot reunion is impossible. In 2007 the band lost their singer, Kevin DuBrow, to a drug overdose. The documentary follows drummer Frankie Banali, a single father, as he tries to pick up the pieces and move on.

Some people seem legitimately angry at Banali for continuing Quiet Riot without DuBrow, calling the new lineup nothing more than a cover band. Other fans seem thrilled at the chance to hear 'Cum on Feel the Noize' live, some for the first time in 30 years, others for the first time ever.

For Banali, though, it's simple economics. "This is what I do," he says at one point, exasperated with the criticism leveled at him. I spent the weekend wondering why the Mad Season reunion minus two key players was a victory and the fact that Banali can still feed his kid by plying his trade with a new singer is a defeat.

I should have an answer for you, but I don't. Maybe the promise of a one-time special event makes the difference, like Led Zeppelin's reunion gig at O2 Arena. After all, Layne Staley's main band, Alice In Chains, suffered Quiet Riot-like criticism when they hired singer William DuVall to fill his dearly departed shoes permanently, but people gushed over Zep's gig.

Perhaps there's wiggle room in the fact that both Mad Season and Temple of the Dog were "supergroups," combinations of established artists coming together for a single record. Some music fans get very emotionally invested in their favorite bands, even more so as the years pile up. Longevity is a liability for most bands with lineups changes. For every AC/DC that survives a front man change, there's a Doors that can't.

This is a phenomenon unique to popular music of the last 50 years, this notion that with rare exceptions only the original artist is allowed to perform a particular song -- all others need not apply. In fact, even that a band has to play on its own records, much less write its own songs, is a post-Beatles phenomenon.

Prior to the Fab Four changing the playing field, A&R men ruled the music world. These were the label executives who matched artists with songs (repertoire) from professional songwriters. There was no shame in that game -- connecting a good song to the right artist was a skill.

Even iconoclasts like Jimi Hendrix recorded what in previous decades would have been labeled "standards." One of his best loved tracks, 'Hey Joe,' was written by Billy Roberts and recorded by literally hundreds of artists. And yet, if a band plays 'Hey Joe' today, most people will rank the performance, at best, as a good cover of Hendrix.

The Beatles really did change everything. They were such a dominant force in the music business both artistically and commercially that most everyone adopted their model. Writing your own songs and playing on your own records went from nice to haves to need to haves. The music and the performing artist became synonymous.

Songs not performed by the original artist -- and by "original" I mean "the artist who originally made it famous" -- were met with disdain. Covers were the domain of variety show acts, bar bands, and Elvis impersonators. Concessions were made for artistic interpretations, of course. Siouxsie and the Banshees gothing up 'Helter Skelter' was cool, but a note for note remake right down to the blisters on Ringo's fingers? No way.

But why? Nobody outside of the studio ever had the pleasure of hearing the Beatles tear through 'Helter Skelter' live. Why should that song in its original form be trapped in amber like some kind of -- well, some kind of beetle -- just because its original artists have shuffled off this mortal coil?

We don't hold classical music to this standard, nor do we insist that only the original cast of a musical can perform its songs. If you love the music from 'Cats,' 'Showboat,' or even 'The Book of Mormon,' you can attend and enjoy a performance at your local theater, but God forbid that Quiet Riot or Alice In Chains visit your local state fair with new lead singers.

We have over 60 years of rock history behind us. That's millions of songs -- millions -- and of those, millions can never be performed again by their original lineups due to age, death, retirement, illness, or legal battles. Even band members moving onto other careers prevents the overwhelming majority of songs from the rock era from coming live to a stage near you in their exact original form.

Good songs outlast both their writers and their performers.

Good songs outlast both their writers and their performers. That's a wonderful thing. John Lennon wasn't immortal but his work is, and so is Layne Staley's, Kurt Cobain's, Nick Drake's, on and on.

I want to see more live performances greeted with the enthusiasm of last week's Mad Season gig. Keep the music alive and on stage where it belongs. I can't imagine that the composers wouldn't want it that way.

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