I first posted 2 years and two days ago and with my memory have no recollection of what it was.
I do remember lurking for several months and watching the development of the PiP. Although I have learned quite a bit about mileage programs for sure my most pleasant and unexpected gain is having met kindred souls who have become the balm/bane* of my obsession.
And my biggest regret is that I waited and watched the PiP happening and did not participate.

*both words for the exclusive use of svpii