Wondering why one might use three layers in Finale? Here's an example from Peter Thomsen over at Finale's forum:
Thanks for the great example! To separate the voices even more, I'll try changing the stem direction:
There, what do you think? Let me know.
Here's another example of a situation in which one might use three voices (as per the Finale forum), however, I haven't gotten it to work yet.
The 8th note low a in measure 4 does not play in playback, no matter what I do. As a workaround, I tried inserting a whole note low a in layer 3, thinking that I would make it invisible, and that it would play in playback...but it did not work...off to the forums (http://forum.makemusic.com/default.aspx?f=5&m=136043) for an answer!