gmirror, identical priority values

[Carl]

What are the consequences of creating a mirror provider using gmirror 
with more than one consumer having the *same* priority value. This is an 
easy mistake to make and it can't easily be fixed because gmirror 
provides no way to change priority after the fact. For what it's worth, 
I'm using the round-robin balancing algorithm, but as I understand it, 
priority isn't just used for the balancing algorithm.

Note how even documentation in FreeBSD Diary makes this mistake:

http://www.freebsddiary.org/gmirror.php

And it's easy to find other folks in the mailing lists making this 
mistake too.

Carl                                             / K0802647