private attributes can't be bound

[kociak]

private attributes can't be bound. I think this is an issue with name mangling.
This is an issue when you want an UI to reflect the state of a class that can be scripted but you don't want to give full power to the scripter (although name mangling is just a convention and therefore not perfect).
Example. Assume you have a class that reflects some parts of the microscope, some are critical, some not. For example, one property control OAV opening, some other the defocus. The OAV one has to be private (we want to avoid opening the valve improperly from a script), but the defocus can be public - one can control the defocus from the script. However, both property must be appearing on the UI (for example, a disabled check-box for the OAV, and a text field for the defocus)