gmic // color presets (filmic)

Hi,
do you know, how the film presets (e.g. color slides by Pat David) are developed? Are the color presets based on real color slides (or negative film).

And which is the “best way” to use it in darktable, which modules are recommended? base curve, filmic or nothing from both, only whitebalance, exposure.

Thanks for help!

Best Regards.