Geno will hang it up when he feels like he has nothing left to offer and his health is good. As many have posted he has zero left to prove and his legacy is solid regardless of what he does from here on out. From a succession point of view I would like to see CD take the team over for a couple of years to soften the loss of Geno on the sideline. No other coach will be able to handle the expectations after Geno and having another person have success will really help whoever the long term solution happens to be.