Playing with a Rail Driver and using a tap controller wheel can be touchy. I do wish that DTG would set up the BR110 DB like they have with the BR 204 where the entire throw of the throttle lever is devoted to the speed control https://100001.onl/. On the BR 110 you only have half of the throw and the back haff is not used for anything, so it is available to be used for better control.
The back half is used for the dynamic for the 110. Whilst I agree with your sentiments the rail driver current set up for the 110 is problematic, same goes for the n-wagen, 612 and to a lesser extent the 363. Even the amazing G6 suffers from a below average RailDriver port although better than the others listed.