It is afterall HIS choice as to what he does with HIS career. ALL of them said the 2007 O2 show was woderful, but visibly draining. They are the BEST band I agree but they are also in their 60's. You could tell from the O2 show that by the end, he stretched his voice to its limited, although it was still spectacular in the end. As a die hard ZEP fan myself, I still have to wonder if "doing it again" would be for their benefit or ours?