It seems like a lot of people don't really consider what it really means to be "modal," and when it comes up, I describe it something like this:<p>A modal is not, in itself, an overaly, window, frame, etc. Generally, it really shouldn't even be used as a noun. Modal describes the state of the interface. Most interfaces allow for multiple user interactions originating from the broader interface, i.e., it is multi-modal.<p>Sometimes, it is necessary to put the UI into a single-purpose state, so, in a single mode. This is required when two interactions can interfere with one another. When one interaction must not be interrupted by another, we must go modal.<p>The author seems to be chiefly complaining about unnecessary modality and the way that gives rise to clunky UIs that don't allow for things like linking. That's rooted in conflating on-screen, 3D elements like overlay dialog boxes with the concept of one of some interface being modal. An example of this would be an interface with a item list that, on item selection, conjures a modal overlay dialog box with the item details. In the base case, there is no dependency problem here, i.e., it's an entirely acceptable design to allow a user to view the details of two items at the same time, and therefor it doesn't call for a modal detail interface.