There is more to it, though. If you surrender but change your mind and plug your keyboard back in, it resets to telling you how many devices there are.
I avoided checking the source code specifically to avoid spoilers, so I ended up spending about 10 minutes to create a vbs script to open the game and wait a few seconds for me to unplug devices so it could SendKeys for me, only to realize later that there's no code to handle that.