There is a definite connection to the spark plugs being changed as that's exactly when I inherited the rough idle shakes an shivers. Its got to be software related as between us we've had everything swapped out including inlet valve cleaning. It seems when the car gets too used to the gap on old plugs it struggles to readjust when the new set goes in.
I've had every adaptation reset with no improvement, it also strange that it just a rough idle for us all n no boost misfires. If we all keep digging we'll get there soon enough!!