"Also, I gather that there are very few who really understand this issue, much less that the 2 sets have different purposes (which is not to say exclusive purposes)."
===page 278===
[...]
proceedings of the provincial congress of sacred music held in Padua from June 10-12, 1906:
[...]
These proceedings established two important points. First any signs
used must be separate from the notes themselves. Second, such printings
of these signs are private editions and need the approval of the local bishop.
Much of the confusion in the literature on this matter was caused by a lack
of clarity on these two points. There is evidence of this in the letter of October
11, 1906, which Caspar P. Koch, Pittsburgh, Pennsylvania, wrote to Dom
Pothier:
===page 279===
[...]
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