I recently downloaded Camille Saint-Saëns' lovely Valse nonchalante—the Durand First Edition (1898)—from IMSLP. All the upper-staff reminder accidentals are placed above the staff. I don't remember seeing this style before.
I don't have that many Durand scores, so I don't know whether they've maintained this policy. On the one hand, I like it because it distinguishes reminders from true accidentals without the clutter of parentheses. On the other, placing them above perhaps makes them a bit too prominent. (I assume reminders in the lower staff would be placed below.)
I'm curious whether any other publishers adopt this style and what others think about it.
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Note that this placement is, of course, practical only when there is a single note. In his Valse canariote (also Durand) we have the usual parentheses (and smaller type) in m. 3 here:
It may be for this reason that we rarely encounter this placement in modern music.
