As judging by the responses so-far received by this writer (one
published response and several of others by way of private inquiry)
since that posting of the one image, there seems interest aplenty,
regarding the subject of how 'it' was done.

In my view, the discovery of this one page constitutes a signal
event on the way to true understanding, as shed from tedious
speculation and mere surmise.  Included, at the link below, is an
image of the whole page as provided by International Arcade Museum
at https://mtr.arcade-museum.com/MTR-1925-80-3/MTR-1925-80-3-31.pdf 

As can be seen at some point it suffered water damage, as running
of the cover page's fugitive ink color has stained certain areas but
only wrinkled others.  (To be noted also is the fact that many of
the gorgeous covers display this same damage too.)

Within the area of most interest -- that providing sight of the marked
area of "the master record" -- can be seen that pink overlay of color;
however, this does not cloak what is there that is informative.

As mentioned in Part 1 [190819 MMDigest], the area being pointed-to
by President Heaton at the extreme right margin, contains treble-side
seismographic inscribings (would he have been pointing to nothing,
as the caption contrarily states?), these being obviously too light
to be seen in this low-resolution, sampled snap.  It is quite likely
that the original 4" X 5" fine negative contained such evidence.

As was correctly noted in the reply in 190821 MMDigest, it seems not
unlikely that the printing department would have emboldened some,
the otherwise nearly invisible punchings or markings, for sake of 
simple visibility.

Although in the case of the one artist I ever queried (possibly _ever_
for any?) about his recording session at Welte-Mignon (Licensee),
namely Bernardo Segal (or Bernard Siegle as he then used) it was to be
a week before he returned to hear his records and, stated explicitly
that _no_ editing was required of him.  Interestingly and tellingly,
when queried on this point, Segal displayed a look of puzzlement just
before answering.

Matilda Locust (of "The Five Locust Sisters") who had made a Welte-
Mignon (Licensee) record-roll, in the early 'Seventies came to my
townhouse in West Los Angeles searching after her one title, which I
felt very bad about because not having it. (DANG!)  More unfortunately
still though, was that I did not ask of her also, this same key
question.

Also hanging-out in Hollywood, teaching students at this time, was
none other than Marguerite Le Grand herself!  Well, the 1927 catalog
did state that it was "in the far West" to whence she had repaired so,
as armed with this information bit, I just picked up the phone book
and there she was!  I spoke with her twice.  'Twas only youthful
stupidity and laziness, one supposes, that conspired so naughtily to
prevent this writer from going to Hollywood for a visit and, knowing
the right things to ask.  (Another DANG!)

Welte-Mignon (Licensee) alumnus Ruth Bingaman Smith was around for a
quite long-while.  Might anyone have asked of her such key questions?

Jim Miller
Las Vegas, Nevada

 [ Auto Pneumatic Action Co. Holds General Conference 1925
 [ http://www.mmdigest.com/Attachments/19/08/22/190822_135106_MTR%201925-80-03%20(31).jpg 

 [ Thanks to the Musical Box Society International (MBSI) and
 [ Arcade Museum for making the Music Trade Review and Presto
 [ magazines available for on-line research.  -- Robbie