The Liam Gallagher of old, with his shrapnel wit and swaggering crusade against being “suckered in by the dickheads”, would have tossed a grenade into the editing suite rather than sanction a doc that is more extended corporate rebranding exercise than it is rock’n’roll. But as this plodding portrait, which follows Gallagher post-Oasis, is at pains to point out, he is a softy at heart who loves his mum and his kids. Yawn. Surely the whole point of Gallagher is that he’s a raging maverick with no patience for industry spin, who thrives on grudges and who would never, ever, allow a director to play Ave Maria over a montage of a studio recording session.