“And I would never lose my head tonight.” Yeah, whatever, Bethany Cosentino. On her main group Best Coast’s debut, Crazy for You, Bethany was totally optimistic. Yeah, she didn’t brush the dust off her shoulder on that record so much as add it to the dust sculpture of the guy a couple houses over who would not pick up his fucking phone. So is her guest turn on “Buy Nothing Day” a little unconvincing? Sure. But there’s no denying the unbridled pep it exudes, a brilliant summation of all the other unbridled pep The Go! Team supply throughout Rolling Blackouts. Cosentino’s dour tone is the exact amount of cynicism needed to humanize the track before it’s off like clockwork for three glorious minutes of verses, pre-choruses and choruses that seem to one-up each other in rapid succession. Every time I play it, I’m as bouncy as the bass line. Put it on while I play hopscotch and watch the sparks fly.