Yeah, what I actually use is a script that I wrote which looks at your party member's targets, picks the one most likely being tanked, and if none of the party member's targets are set or none of them are enemies, then that bit is run to select the actual nearest target. When using this script, I mouse select the target to sheep, then wait for my group to attack something, hit the hotkey for my script and start casting. I can post my script if you like.