Seems like turn-about is fair play: I know that RW couldn't prevent PF from touring (without him), so it stands to reason that DG cannot prevent PF from touring (without him). I suspect, though, that neither RW nor DG really want to tour with PF. The way the contracts are written, they end up having to give over too much of the take to their partners, instead of keeping the vast majority for themselves. Besides, neither RW nor DG need the money, so if they're going to spend the time and energy to tour, they'll want to do it for the glory, and so why share that if you don't have to.