Hello, I know this is an old thread, but I wanted to bump this topic because I have run into the same problem on my current project and there still doesn’t seem to be a convenient way around this problem.
I am notating a SATB choral piece with a substantial piano accompaniment. I’ve notated the vocal parts on 4 staves and have used system-by-system condensing changes along with selectively deleting lyrics from some voices for certain passages to get the condensing feature to behave as desired (sometimes showing 4 staves, sometimes 2, sometimes 1, depending on what the voices are doing at any given time). Much of the piano part is on three staves and isn’t particularly useful to the singers so I’ve omitted it entirely from my vocal score layout and I’ll be making a separate score for the pianist.
My vision for the piano score is to have the piano part at full size, and then include the choral parts as 2 condensed staves at 60% staff size above the piano. Currently there is no way to achieve this, unless I re-notate the choral parts of the flow on a grand staff as two new players (or perhaps as a piano with lyrics) just for the purposes of including them in the piano score layout.
I’d be interested to hear if anyone has any suggestions. I can’t wait for the long-discussed improvements to condensing for choral scores. Condensing is such a great feature when it works, but it does take some unintuitive steps to make it work elegantly for choral music.