Originally Posted by Aristophanes
Yep, I know - but you can see for yourself that it won't work with the current firmware because the camera disables all external controls and powers down the metering system as soon as the USB cable is connected, when set to PTP mode. Hence, there's no way to take a picture.
For it to be useful for tethered shooting, Pentax would need to change their current firmware so as to allow the camera to shoot while in PTP mode, which is something it can't currently do.