Hi kmoor
This is a feature. The idea is that if the screen is set so dimly that it cannot be seen, for example in bright sunlight, you can hold down the surface button to restore the screen brightness to a level that should be visible in any environment, and from there set the various dimming controls as desired. If you need to control the brightness in a normal scenario, it’s only one or two extra actions to press the ‘Surface’ button normally, then go to ‘Control’ (selected by default anyway), and ‘Dimmer’.
Hope this helps
– Jeff, A&H