That's an interesting idea. You can already sort of queue up a preset by using the right footswitch to increment up to it and using the active button to switch to the new preset when you want. But you're right that there's no way to get back to the last loaded preset easily. Most tv remotes have a function for going back to the last channel you were watching. I suppose that this function you're describing could go back to the last loaded preset and could be used to toggle between any two presets.