Everyone knows performance tuning of a system is one of the thankless jobs, but it really interesting and he who does it feels the joy of it. Challenge is there in any tuning job.
But the new challenge is to make a non technical representation of the same. A non technical representation, a model, which shows with a very very thick outline the past and the present effect of the tuning.
And it is a bigger challenge when you need to devise some method in an SAP environment.