On the topic of SCSI voodoo -- the rules for configuring SCSI chains are very fixed and understandable. And when a SCSI chain is configured according to the rules, it almost always works properly. I've never seen a properly configured SCSI chain fail to work properly.

SCSI Voodoo occurs, not because properly configured SCSI chains don't work. SCSI Voodoo occurs because improperly configured SCSI chains sometimes/often work, and then later they don't work, and folks wonder what went wrong with a chain which was never configured properly to begin with.

I wrote some long tutorials on SCSI chain configuration, especially on mixing narrow and wide drives on the same chain, over on Usenet in the comp.sys.mac.* hierarchy, back in the late nineties.