Ah, I would love to do that! Unfortunately, the N900 can't actually see the TV (or whatever device you're pointing it at), so it has no idea whether or not a keyset has in fact triggered the device.

Actually, I was originally worried that the keysets would go by too quickly; my first interface only allowed you to step through the keysets one by one, rather than kick off a fast sequence and force you to hit the "pause" button as soon as something happens. In fact, those original controls are all still there; if you notice that a keyset worked, you can hit "pause", and then keep hitting the "prev set" button until you get back to the keyset that worked.

Also, you can hit the "edit keyset" button to make the keyset you've found a "favorite", and continue on with checking other keysets. So you don't really need to write down the name of the keyset when you find one.