Just an FYI, I recently bead blasted a gen Porsche Design PVD chronograph. The PVD was in poor shape and my intent was to blast it all off as it looked like it was painted, it in fact was not painted, just 25 year old PVD showing the wear of photojournalist wearing it to hell and back. Have a look.
Anyway, while blasting this case, I did notice that part way through the process I had blasted the remaining PVD into a new soft bead finished PVD that was very similar in look and feel to a davidsen PVD case. I didn't take any pics unfortunately as my goal was a pure bead blasted finish and I was part way through the work. The finished bead blasting was quite pleasing and the watch came out excellent.
I do believe that with a fine media that isn't at full velocity, ie very close to the gun, a blasting of the PVD surface could be made to happen. The key however is how much PVD you have depthwise to start with.....