For reference, I think `clearGui` is not needed for UI elements that represent TestElement properties. At the same time, clearGui might be needed to reset UI state which is not connected to TestElement properties. For instance, if there's a "tabbed pane", we might want resetting the UI to its initial tab.
However, I think we should remove boilerplate code like
someField.setText("") from our clearGui implementations, see more details
in https://github.com/apache/jmeter/pull/6199
Vladimir
