I have to agree with the concerns expressed regarding the long term
reliability of such a system, with all of the vagaries of climate and
storage conditions to consider. In addition, however, it seems to me
that its primary failing is that the system depends upon heat to
retune.

Now we know that heat applied to a piano string will cause it to
expand.  And so it will drop in pitch. This is almost always the exact
opposite of the effect needed to bring the piano back to correct pitch.
So we have to make the string cooler if we are to raise its pitch.  So
we need to heat it before we can cool it.

Sounds daft to me.

And of course if it is to maintain its new pitch we must keep it
heated.  We cannot allow ambient temperatures to cool it further,
else it will not only be the air that is sharp!

At the end of the day this one will go the same way as the Mangeot
Dual-keyboard with reversed scales for Right and Left hands, and the
curved Clutsam keyboard.  Or, more pertinently, the piano that had
tuning forks installed instead of strings.  Now that really was
incapable of getting out of tune!

Interesting ideas but never likely to catch on commercially.  Still,
one must not be cynical.  Where would we be without Mr. Hawkins from
Philadelphia?

Roger Waring - The Pianola Workshop
Solihull, United Kingdom
http://www.pianola.co.uk/