Oh, I did the 60 - 20 braking thing until I could feel the brakes fading, and then drove normally for a bit to cool them off, then I did it a few more times, then drove normally again to cool them off.
I think it made some difference.
As it was the dead of night I did some testing, there are no worrying vibrations at all when slowing from 70 or 80 to a standstill, there were before. However when slowing from around 100 to a standstill, the car is stable down to about 70, then whole car shakes violently when decelerating through 70 to 40 or so. I don't really understand this...