Down for a descent. Up for pedalling. Watch what the remote does.
Move the saddle. The remote opens while you change its height.
Saddle raised. The height is held.
What happens
In this generic continuous-adjustment example, holding the remote allows the height to change. Rider weight lowers the saddle; unloading it allows it to rise. Releasing the remote retains the chosen height.
While you move the saddle, this example holds the remote for you. The movement stands for loading and unloading it. The drawing shows neither Duncan internals nor a servicing procedure.
A simplified illustration, not an exact model of your equipment.