bad tech puzzler

[Tvak@AOL.COM]

I've seen some pretty strange things the last couple of days.  Tuned a 
Steinway A the other day.  A#0 had a replacement hammer that belonged in the 
7th octave.  No wonder it didn't sound like it's neighbors!  The rest of the 
hammers were filed so poorly that the guy must have been drunk.  There wasn't 
a level surface to be seen on any hammer, every one angled down left or down 
right.  Then I noticed the strings on F6 were crossed on the pin side of the 
capo bar.  The left string crossed over to the center tuning pin, and vice 
versa.  

Then tonight I played at a restaurant and was told that the piano was just 
tuned yesterday.  There wasn't a unison on the instrument.  (Some were pretty 
close...some weren't!)  I looked inside and I saw a mute sticking in between 
two strings on a trichord unison (I use the term loosely).  So I figured it 
must be a new string, muting out the left and center strings so that they 
wouldn't drift out of tune.  At the end of the night, when the last table had 
left, I looked at the string and noticed that it wasn't new.  So I took out 
the mute and found the outer two strings were in tune, but the center one was 
SHARP!  

Why would someone mute out the left and center strings on a trichord (not a 
new string) and leave only one string sounding?

I did tune the center (sharp) string and there was no inharmonicity or other 
problem.  It tuned up just fine.  The pin wasn't loose.  Everything seemed 
just fine, but for some reason the guy muted it and it's left neighbor.  

Could there be a rational reason for this?

Tom Sivak