The point is you don't want to do this on a SCSI bus which is not
quiescent (this is a problem especially on the bus which has the internal
disks connected). If it is, and the peripheral is switched off during
connect/disconnect, not much can happen. My old AIX box had a second SCSI
adapter which only connected to the peripherals, and I never fried
anything. And I plugged a lot.
-- New crypt. See /usr/news/crypt.