Is there anything you can do about these clashes?

Yes, thanks for spotting that, GerardH. A corrected copy is here, and if you notice any more details to fix, please let me know.

And yes, Palestrina, I've been transposing some to keep the ranges manageable for our schola of men.

Many of us are grateful to you and others who re-engrave NOH accomps. Thank you.

These are useful, but they don't exactly reinforce the Solesmes rhythm. In the Asperges, the chord should change on the ictus at the last note of et instead of mun-, likewise at per ni-. Counting nivem as 1-23 is a more serious departure from the Solesmes rhythm because it violates the third rule for ictus placement, which requires an ictus on the first note of the pes at -vem, since there is no other known ictus taking precedence over that placement. As a singer, I would find it unsettling to be counting 123 and hear a chord change on 2 that also doesn't align with the chironomy. You've done good work here, but if your objective is to Solesmesnify it, why not go all the way instead of something that's neither fish nor fowl?

Although I recognize that long-short-short is what many actually do at da- and ba-, it would be better to use a tenuto mark, likewise at the final alleluia of the Vidi aquam. The ictus in the mode VII psalm verse is on the upper note; it would be helpful to have a rest notated before Miserere and Gloria. There's some flexibility in the guidelines for ictus placement, but choosing the word finals at secundum magnam would be more standard. Dextro and dicent are disaggregate neumes, so the ictus and chord should be on the first note. Same suggestion as above about a rest before Confitemini and Gloria. The chord changes at ejus and amen highlight another interpretive difference between NOH and the Solesmes method.

For reference, I'm attaching these chants from the modern notation edition of the Liber Usualis, edited by the same monks who edited in the Gregorian notation editions. Note that later presentations of the Solesmes method (certainly by the 50s) treated rests before bar lines as quarter instead of eighth. At the end of the second line, you have a quarter bar line in the melody and a half in the accompaniment.

https://drive.google.com/open?id=19pW4BaqtPzpRMuOmOssIIsSVXpl5rpwl&authuser=2239545%40gmail.com&usp=drive_fs

Here are Masses XVII and XVIII for Lent.
(Note: this is a draft.)
https://forum.musicasacra.com/forum/uploads/FileUpload/5c/118c47e446256c2ac845d96478a0ee.pdf

As you said, the original NOH didn't follow the common Solesmes interpretation of the time. There are differences between the Belgian, French, and German styles of interpretation and accompaniment, which Ostrowski has written about here, here, and here. I think a true Solesmes-style accompaniment, where the chord changes often don't coincide with word stress, is more jarring to English speakers than moving chords away from the ictus. It seems like some of these chord changes are trying to emphasize melodic peaks rather than text or Solesmes ictus placement. Would you say that's accurate?





The chord change at the end of eleison is especially disconcerting. In the Sanctus, the box at in nomine should be only over the first note; but I can't easily correct the marking after the file has been saved and closed, sorry.