Thank you for explaining the relevance of the Gould excerpt, Daniel, and the issue itself. I am glad that this will be addressed.
So the program always starts with up-turned ties independent of stem direction. And that is why the problem doesn’t seem to arise with up-stem chords, which was puzzling me: the tie is now on the note head side of the chord, where an up-turned tie would be expected.
I tried the example in Finale, which, as you said, has the same issue, and which also “fixes” itself when the down-stemmed chords are flipped to up-stems.
That’s a very interesting point, Mark_Johnson. While the standard rules for tie direction in engraving are the same for either hand or staff, Beethoven, for example, often used outwardly facing ties where the stem direction would call for inward ties, perhaps because of this feeling of the two staves of the grand staff mirroring each other:
