Yeah, I was just curious where the particular value of 384 came from.  We don't really have a clear rhyme or reason to the priority values we use at present (most of them mirror the min size) and I've found they don't always do what I think they're supposed to do anyway (how they work is fairly poorly documented).  I had a bit of trouble coaxing partitions into growing to fill a disk even when setting one to a much lower (or higher) priority than others.  I'll take this for a test drive later today and see what happens.