Wave's CSP "plugs in" to the architecture BELOW the CryptoAPI layer. This allows Win32 apps developers to develop against the standardized CryptoAPI and subsequently enable Wave's CSP in order to provide a different IMPLEMENTATION for the functionality requested (in Wave's case, using the TPM).
As I have stated in the recent past, there is a big difference between a standardized interface and the implementation of the functionality for that interface. I am re-iterating this point since this seems to be confusing to some posters here.