No signature required for HOS validation

Contemplating a switch to GeoTab and their platform doesn't have an option to enter a signature every time a driver validates HOS / duty status. Are you buying the explanation or even have first hand experience with a DOT inspection of your logs that this is kosher? I can't find an FMSCA statement that the unique authentication of a driver's login credentials to the elog constitutes a signature when validating HOS daily.

 

Yes, that was the essence of my question, if that's an acceptable way to validate logs
We've only ever used KeepTruckin, which has the functionality of a driver finger signing their logs