Looks like Nvidia is not being very honest here.
CSAA mode: 16x
#of color/z/stencil samples: 4
CSAA can be enabled in one of the two following scenarios:
When the application specifically enables CSAA.
When CSAA is turned on in the control panel by the end user. [...]
It is recommended that applications enable CSAA directly. The process of implementing CSAA is incredibly simple (almost exactly the same as implementing MSAA), and the benefit to your users is enormous; they get much higher image quality at almost zero performance loss, without the fuss and hassle of manipulating the control panel.