There’s something vaguely Cobainian about San Francisco’s latest prodigal punk son gone national, Ty Segall. Perhaps it’s all on the surface — the stringy blond hair covering his face, his nihilistic, alyrical groan, his haphazard yet taut soloing. But there’s a certain grunginess to his band’s aesthetic, also a nuts ‘n’ bolts alignment of guitar, bass and drums. All of it begged a certain question: were we watching something special on Saturday night at The Independent? Was this what it was like to see Bleach-era Nirvana in a Seattle club in the mid-‘90s, when all that mattered was the channeling of angst?