One thing that should be noted is that under the concept of a UNIX username is a UID. Your UID is what really identifies files as belonging to you, etc. So if you have two systems and the same username on both, it doesn't guarantee that you will have corresponding privileges (as far as I can figure). This has been a real pain since I used the removable home directory setup.
Since I've been using this setup, I can actually wipe users from systems without any real downside. So I'm drop my user on one system, recreate it, manipulate the UID and home directory values in NetInfo so that they match my other system and see if that straightens everything out.
To the author; please post a comment about this issue!
Oh yeah, I've also had weird residual /Volumes/ listing for drives that have been put away properly and unhooked from the computer. The result is that when I rehook the firewire drive up, from the command line (ls) the drive name is listed (and is empty), but the new instance of it is name "drive name 1", thus throwing NetInfo off. I've ended up having to manually "rm -rf drive_name" and then reboot. If I don't do anything the old instance of the drive_name persists beyond reboots even!
Any clue about how to work around this?