Thanks, the increment in there was a test of exactly that, and I did indeed find that it never incremented. Obviously if I can get the index of the current point then the incrementing is totally irrelevant (sorry if that confused the question!).
I love the parallels with Houdini in PCG, and general access to the current ptNum is such a useful piece of data it would be great to expose it wherever we might do work on a point. Total number of points might be useful too.