Hi all, >> I am pretty sure this is not a standard thing. > Actually, it is a standard thing, at least in piano music. Attached > is an example from Schumann's 'Humoreske' (Henle Urtext).
Fascinating! In 40+ years of playing piano — including a Bachelor's degree in piano performance, and lots and lots of composing and performing of modern music — this is literally the first time I’ve seen this notation. I love learning new things! =) Kieren.