I compared how well the Nikon D800's can take extreme adjustments and if there's difference between 12 bit and 14 bit raw files and when is it okay to use the lesser bit depth. Below you can observer how the shadows get abruptly clipped in 12 bit files when adjusting the by ten(!) stops in Raw Therapee since it does its magic in 32 bit float ensuring maximum image quality. In 14 bit raw files there's still some detail left although the image gets a tad noisy. However, if shooting above approx. ISO800, there's no discernible difference between the formats, the camera's noise floor rises so high that the clipped parts of the image are drowned in the noise.
(When measuring the dynamic range of digital sensors, this is it. The difference is almost always in the shadows since linear sensors such as CCD and CMOS always clip when the photon well of a sensel is full or ADC gets clipped.)