By Mark Jefferies Jon Bon Jovi says he will quit touring if his singing is “not great” after having throat surgery. The 62-year-old rock star is still in vocal therapy after undergoing surgery in 2022 and is “good” with the idea of quitting life on the road if he discovers things are not up to scratch. He said: “It’s the parallel storyline, right? This is the first time I’m saying this. If the singing is not great, if I can’t be the guy I once was … then I’m done. And I’m good with that. There is a big difference between being in a studio and going out on the road. We have just recorded a new …