Monday, August 21, 2006 Any concert tour called 20 Years of Rock And Roll promises an enthusiastic celebration of the music of yesterday. In the case of the Poison/Cinderella double bill that played its laser show-loving heart out at Sound Advice Amphitheatre on Sunday night, that meant plenty of loudly shredding guitars, hair that was sprayed to the heavens and all manner of questionable but era-appropriate mesh. But there was, in the crowd of 30 and 40-somethings reliving their late '80s rock dreams in this Gap khaki age, at least one symbol that proved there was still a genuine mood...