Part cues have many very useful applications, many of which you wont think of until you are in need. A couple basics I can think of now are:
-To
fade different channels at different rates--if you were to try to write something like two cues and auto follow them (assuming we are talking a non-tracking board) then once the second
cue starts it takes over the
fade time of the channels in the initial
cue. i.e. you can have
channel 1
fade up in a 5 count and
channel 2
fade up in a 10 count, both starting at the same time.
-Similarly, you can put a wait on certain channels, i.e. you can have
channel 1
fade up in a 3 count while
channel 2 waits for 2 seconds before starting to
fade up in a 3 count.
All and all it is a very useful tool on non-tracking boards because it allows you to do many things that are inherent on a
tracking board.
Once you get a hang of them you will find tons of places to use them.
-Tim