Problem with Explode

• Nov 20, 2020 - 11:08
Reported version
S4 - Minor

I have a piece of music (See file Start) where the top stave contains both First and Second Tenor parts. The lower stave contains First and Second Bass parts. I wish to have each part on its own stave.
1. I add a new stave below the current top (Tenor) stave
2. Add a new stave below the current bottom (Bass) stave.
3. I highlight everything on the top stave
4. Select Explode from the "Tools" menu and I then get the top stave now contains everything for the first tenors (Voice 1) and the second stave contains everything for the second tenors (Voice 2).

That's what I expected.
Now for the Bass.
5. I highlight everything on the third stave (which is the one having both First and Second Bass parts)
6. Select Explode from the "Tools" menu and then I get stave 3 containing the notes for the SECOND Bass (Voice 2) part and the 4th stave containing the notes for the First Bass (Voice 1) part. Staves 3 and 4 seem to be the wrong way round.
I had assumed that "Explode" leaves the first voice on the original stave and places the second voice on the new stave. That's exactly what has happened with the previous 61 songs I've reformatted but with this one it's voice 2 that's on the original stave and Voice 1 that's moved which is confusing.

The difference between this song and all the previous ones is that there are no notes for voice 1 in the first bar.

Is this how Explode is expected to work?

I'm using version on Win 10Pro


Type Performance Functional
Workaround No Yes

The normal behavior of explode doens't involve voices at all, it's for separating notes of a chord (which is by definition notes in a single voice). But we do make a special exception, if the first measure of the selection contains multiple voices, we switch to a different algorithm that separates by voice instead of by chord. And in that case, it seems we take the first note we find as the first part. suspect think this was to produce the expected result in some special case or other, I'm not really sure, but anyhow. definitely seems not the right choice here. So probably there is some way to be smarter about this.

Meanwhile, workaround is to exchange the voices afterwards with Tools / Voices. Or add a dummy note to the beginning of the first part.