I tough that this PICKUP MODE was one basic standard feature included in the all professional keyboards, we have this on MS from 4 years.
On MS is working on this way:
The black slider image is on the relative software data value.
The Green ghost pointer is on the relative Hardware slider position.
the REED ghost pointer mean that the relative Hardware slider is Linked at the same value of the slider data software.

So..the hardware slider does not change the software data slider until you get the hardware slider to the same position and then will automatically Link.

here a picture, maybe you can understand better: