It can be a solution to the - 'enum is easy for developers to use, but isn't flexible' problem. It is also a lot of work.
You could have a custom hardware driver step type that brings up a configuration dialog box. The dialog box checks the available hardware drivers, and displays them to the user (child class names or 'friendly' driver name). When a user selects, say NIDMM driver, the dialog box then lists the available functions for that driver - as a string based combo box. Depending on which function/driver you select, you get different configuration screens. Like I said, its a lot of work, and really goes back to - how much time do you want to spend on this, and how powerful do you want this to be.
