The guitarist joined Stone Sour in 1996, just before the band split. He signed up for Slipknot in 1999 then returned to Stone Sour in 2001, remaining until he was dismissed last November towards the end of their touring duties for The House Of Gold & Bones. The lineup change wasn't confirmed until May.

Despite saying he was "not happy" about the move, the additional free time gave him the opportunity to focus on material for Slipknot's long-awaited album .5: The Gray Chapter.

Root confirms the situation had been playing on his mind. He tells Revolver: "Slipknot made it possible for Stone Sour to have everything that is has. And there were people in Slipknot sitting idly, waiting to do a new album. I had fans asking me every day, 'When are you doing Slipknot?' It just seemed like it was in the air.'

"It became apparent to me near the end of the album cycle for The House Of Gold & Bones that it had run its course. The band kept pushing for more dates and I was like, 'It's time to stop.'

"Essentially, in November I found out that Stone Sour wanted to do some more shows, and they didn't want me to be a part of it. I guess you could say I was given the opportunity to start the Slipknot album, to put it nicely."