"The timing wasn't the best. We had put so much toward the O2 (Arena show). And the three of us were catching up with stuff. It was very good, seriously promising. But there was this other thing going on." Jimmy Page on why Led Zeppelin rehearsals with Aerosmith frontman Steven Tyler didn't work out after Robert Plant declared he was too busy for a reunion tour after the rock supergroup's 2007 gig in London.