It would be nice to have an “instrument” with an invisible line and no barlines, like a washingline to clip not clothes, but text on it, remarks, that only will appear in selected layouts (e.g. only in the whole score, not in the player’s), as an flexible alternative to system text.
As an “Instrument”, one could have more then one of this lines… one above all for a conductor, another for the singers…
I quite like this suggestion. It could be linked to an ‘arrangement’ track in Play mode.
Yes, it could be called a “tag line”!
Great idea!
This would also be great for music-to-picture work.
And Steve - forgot to mention - you get the award for most “intriguing” title of a post. I’m sure everyone reads it and says “what… !!!” Ha Ha 
A clothes line instrument? Isn’t that known as an alto flute?
But isn’t it the drummer who is usually “hung out to dry”!