Marimba: one- or two-line part, switching, hiding staves
I have a score to write where I occasionally need two lines for marimba, but mostly only one line would be enough, though that line would have two voices. That is how the composer has chosen to write it.
The percussionist will play marimba and several unpitched instruments.
I don't know
a) whether it would be a good idea to write the marimba part on two lines even when one would be enough; and b) would it even be convenient to do after already creating the instrument "marimba - two lines". Will it hide the other staff when it is empty?