With a FBW throttle it would be fairly easy to program in you just need to keep pumping fuel through the system when the throttle is closed but it is a bit like smacking the turbines with a sledge hammer to crack a nut.
Yes I agree. Half of the job is already done with the recirculation system (i.e. the DVs). This prevents the turbos stalling. If all it takes to keep the exhaust fired up is to <beep> the ignition then this is all possible with a simple ECU remap.
I imagine the cats would die quickly too...