Thanks @vitor, I got it working based on the screenshots. It's a nice solution, even if a bit hacky as you said in the other thread. Thanks as well @GuiB, your workflow works similarly. I see an almost imperceptible delay between these and the regular Alfred reveal, but they are good enough for now.
@vitor, you're right that it's about maximizing the empty box. While the time would be useful to me (because I'd like to hide my menu), it's easy to imagine other uses; weather, battery, a timer, etc. It's a way to get some kind of immediate information without any extra work (and without installing and learning anything else).