The flaps don't work on a notched system. The flap switch in a Duchess is spring loaded, it has to be held in position. So when held down, the flaps move down. Release it and they maintain position.
When I did my Duchess flying we memorised the time to each setting. It was 4 seconds from 0 to 10, but then oddly only 2 seconds to 20! Flaps were deployed at a time when your eyes were either outside or glued to the instruments so being able to get the flaps to the right position without watching the gauge was vital. A quick glance at the flap indicator was all was needed to verify the setting.
In this respect the model is accurate in how the flaps work.