Well, one of my pieces that I enjoy the tone of but have found 
exceedly hard to play (stuffy) finally met the sandpaper.  This site 
and some practice gave me the nerve (our sheer stupidity) to try it. 
I wont mention the brand because I dont want to offend anyone.  
The .0015 reading (after a dozen readings) was near 4 mm high on one 
side.  All other readings were spot on.  The feeler would just sort 
of slide under never finding a sharp resting point so I assume it was 
a sort of plateau.  

I brought that down even, smoothed out the machine marks on the rest 
of the rails.  I thined the tip and rails a tad.  The result is a 
much easier playing piece.  The palm notes pop out witout effort all 
the way to F#.  Flattening out the tip into the baffle added a tinge 
of needed brightness (dark horn).  The facing is still pretty short.  
Its 20 on a .105 opening.  I may address that later but I dont want 
to push my luck and potentially change the character of the 
piece...or wreck it.  Im assuming The first reading is critical and 
that this was the source of the stuffiness and occasionaly tendency 
to squeal with thin tip mpcs????