Let's say you want to be able to charge key presses, no matter what key is being held down, and then release that charged key press. It'll keep track of the charge time in a variable, and then you can call that charge time in any other event farther down the line.
Another use might be in dialogue systems, where in order to hasten the write speed of text you could just hold down any button or key, and release whatever you held to let it return to normal write speed. It would save having to make an endless OR block with each possible key.
I'm sure there are other uses other folks could come up with too, but that's the train of thought that prompted this suggestion. I figure since it's just a couple variations on the other conditions it probably wouldn't be a big deal to implement, and it would add even more flexibility for such "small" features.
When might you use it?