Wurtilizer Tuning Woes

[atonal@planet.eon.net]

Greetings:
Just a question from the frozen and dry Canadian north about a 
particular frustration in tuning the upper mid treble on a certain 
6'1" Wurlitzer grand, Model G461 bought in the early 80's.  The 
placement in question is from about E55 up past the plate strut in
through the whole next section.  The treble strings were seated, the 
whole piano was given a small pitch raise, then tuned using copious 
test blows.  Three weeks later, then two weeks later, while the 
rest of the piano was solid, this section was not holding its pitch.  
For the most part, flatting occurred, but some unisons could go 
either way.  Any experience and/or solutions to this head scratcher?

On behalf of another technician, brought to you by:
Rob Kiddell RPT
Edmonton, Alberta, Canada
atonal@planet.eon.net