Maybe someone else will chime in here but I think the concencus would be to LEAVE IT ON UNTIL IT GET LIKE BUDDA.
Take it off too soon and the collogen (sp) will not have broken down and it'll be tough.
2004 Weber Performer GREEN
Orange Super-Duper Fast
Taylor Made 9deg. R7TP w/S-Fujikura 6
Rescued 2002 Weber Genesis Silver B Gasser
SJG Tamale Pot Mini Smoker (SJG was a rescue)
18" Gold (rescue) SJS (rescue)
and a Pyro FIL