[Charliey]

Basically, you can set the drives to be master or slave on the drive, but with cable select the master/slave configuration is determined by the order in which the drives are connected to the cable.

it could be useful if you did not want to have to go to the trouble of configuring the master/slave settings. but if you want to have them set to be one way, then it would be more of a hassle to try and get the cable to hook up the right way.