[sdiy] surface of keyboards

[jhaible at debitel.net]

Something completely different, but - hopefully! - DIY related:

So now I have this Technics WSA synthesizer, and I like it's "partly physical
modelling" sound engine.
But I'm not so happy with its  keyboard.  

It's one of the *better* keyboard actions (slightly weighted), but my fingers
are aching after some time of playing. At first I had no idea where this would
come from. I measured the key travel, the length of keys, the force that's needed
to depress a key, the farce that's needed to hold down a key, and all was well
within the range of my other keyboards in the studio.

Then I noticed that the *surface* of the keys, especially the white keys, was
much "smoother" or "more glossy" than my other keyboards'. I thought this
should be an advantage, not a drawback, shouldn't it ? 

But apparently this *is* the parameter that causes my finger problems.
Finger sliding too much across the surface with every keystroke ?
Something like that. I'm alsmost sure this is the problem.

3 Questions:

(1) Has anybody heard of this phänomenon before? Any references about
     a key being "too smooth" ?

(2) Does anybody know what polymers are typically used for keyboards ?

(3) Is there a way to roughen up such a surface? (I have tried a solvent
     for removing price tags from goods, which normally roughens up the
     surface of CD Jewel boxes, but it doesn't work on the WSA keys - seems
     the polymer they used is "too good".

Any ideas ?

JH. (yes, I'm serious.)