It seems to be a very flawed implementation. While it initially appears to work, when any device is paired with the bios, the unit will not boot until you wake up the keyboard and establish a connection. While this may be suitable for some cases where frequent interaction with the bios or bootloader are necessary, it is frustrating for a "normal" user, who only occasionally needs to interact with bios/bootloader.
I would suggest that a tap of the power button during POST should be used to trigger the bluetooth keyboard mode, or a reasonable (short) timeout (say 5-10 seconds) until it continues booting without the keyboard.
Intel improves the compatibility with Bluetooth devices on start up with BIOS version 0028. Check if you are already using the latest drivers.
Your suggestion sounds great, I am going to send your comment to my supervisor; Intel stick developers are interested in customer feedback.