Rock ‘n’ roll is, at its heart, an innately ridiculous undertaking. Which may explain why so many ‘comedy’ acts come a cropper. What chuckle-meister could compete with the (presumably) unintentional hilarity of Mick Jagger, Robbie Williams or Sting? On the other hand, Tenacious D’s Jack Black and Kyle Gass walk the line between heavy parody and reality so cautiously it’s possible to take their knowingly moronic pseudo metal at least semi seriously – get past the clichés and this year’s Rize Of The Fenix contains some cracking fratboy rock-outs. Maybe the joke is on those who don’t see the pair for the exhilarating rock duo they are sometimes capable of being. They arrive in cultist robes and plunge into the new album’s title-track. It’s a little silly, of course, and Black can’t help over-doing the chutzpah – the rom-com star in him you suspect – but, still, what we’ve got here is an entirely serviceable hunk o’ soft rock, several smidgins less ridiculous than the last Kings Of Leon LP. Alas, the number ends with the arena-rawk equivalent of a fart gag as a huge phallic ‘phoenix’ inflates behind the pair. This is what rock nirvana looks like to a spotty 15-year-old. Through the next two hours the quality of the songwriting holds up even if the humour does not (Black has a nerf-ball shoot-out with a roadie dressed as an octopus; inevitably the knob-disguised-as-phoenix spurts white confetti towards the end). ‘Beelzeboss’, for instance, is a cracking salvo of reconstituted ‘70s rock, while a medley of Who standards gives the backing band an opportunity to flex their chops. They close with ‘Fuck Her Gently’, a metal ballad with the soul of a Farrelly brothers movie. It tells you everything you need – or don’t need – to know about why Tenacious D were placed on this earth.