A property can be either read-only or read/write.
Some read/write properties are not meant to be changed by a task or theme. They are defined as read/write to enable to set this property value ONCE. For example, there's no need to change a property value that holds a device ID from a task or a from a theme.
A 'semi-locked' property that is only editable from the device would reduce the risk of a programmer error.
If a task that does 'property change' would not display the semi-locked properties, and also the theme editor would not display them, the system will be less prone to errors.
And of course the SDK needs to support this.
Thank you