Ladies and gentlemen.  I'm aware that I have been taking up
a significant amount of MMD space lately, so I'll keep this short.
I've been sitting, looking at the first lower valve plate that I have
removed from my Aeolian upper action.  Now that the shellac has been
removed from it, it looks bright, clean and shiny.  It's this valve
plate that the lower leather facing of the valve sits on, for
virtually all of its working life.

Having heard dark stories of inferior modern leather tanning techniques,
I'm thinking of giving the plate's top surface a spray with 3M #3900
Clear Protective Coating.  (Not the whole valve plate; I don't want
to compromise the sticking of the new shellac to the metal.)  Is this:

  (i) a good idea,
 (ii) a really bad idea, because in two years the leather
      and the coating will be hopelessly stuck together,
(iii) a pointless and unnecessary exercise?

I will value all opinions.

John Phillips, in Hobart, Tasmania