I'd say, do your best to enjoy it.
I've long given up pursuing low pp challenge myself. Looking hot-shots giving amazing results is interesting, I enjoy seeing those, but I realize it's not for me, I've learned it the hard way.
So I turn to find interesting cars for myself, explore my own possibilities and enjoy it.
Say, the strong rubber band (and such a moving goal) is a known fact, so there'd be much more possibilities, which is a good thing.
I'm not 100% sure but it's quite clear for me - AI might be designed to give me a hard time if I try running repeatedly in the same car and in the same line-up. I've enountered such situation too many times and got tired.
So if I can't win in the first attempt, I just switch to another car. Hard work practicing is not for this event.
Maybe this is the real goal of PD.