Every band reaches a tipping point, where their rapid ascendancy slows, and they enter that “selective appeal" phase. It is the law of diminishing returns, the moment where the number of fans losing interest due to age, indifference and evolution of musical tastes outweigh the accumulation of new devotees. It is the point where stadium-sized bands recede to arenas, where those bothering Apollo's shift to Academies and festival headliners become special guests or even worse inhabit the dreaded "Legends" slot, an abomination designed to preserve the egos of artists yet to fully comprehend their decline. What is astonishing about Slipknot is that 25 years in they are still accelerating. They have a momentum that continues to gather both pace and followers to this very day. For some inexplicable reason, this group of mask-wearing grandad's well into their fifties are still able to speak to the freaks, geeks and disenfranchised of the generations below them.