I may have missed something here, but a qualifying stay as far as VIP status is concerned includes the cheaper rate that may only earn 500 points, or even the few non point earning rates. Therefore, if you have 15 stays at e.g. a bounce back rate, that is 15 stays, and you will get gold.
This is in the HHonors guide, all be it in the fine print.
Off course, when you really show your loyalty and earn Diamond (even by paying the cheaper rates) you get full point credit for all rates. Seams pretty fair to me.
[This message has been edited by Tim_T (edited 11-12-1999).]