I asked Viv about his "employment" with RJD while at a guitar clinic. He told me that RJD got pissed-off about Viv starting his side project: Trinity. He said that RJD refused to let him take the stage with a Strat that had the Trinity logo on it... He then quit Dio. He also said that Ozzy doesn't write his own lyrics... He said that Sharon purchases them!
Speaking of musicians with an attitude... A friend of mine was a roadie for Aerosmith back in the 70's. He said that Aerosmith treated the roadies and production staff like total shit! One of Aerosmith's culinary delights was having a freshly baked turkey ready to eat after every show. While the band was on-stage, the roadies (and production staff) would pull out their cock and balls, crouch down over the turkey, and then rub their genitalia all over the turkey!
Life is grand!