Just to sate your curiosity, hitting left or right on the directional pad is basically the same as Tabbing. It's actually not so bad, considering the issue brought up in the OP. I'm not sure if there is a hot-key on PC (console player since 2.0) for moving backwards using Tab, but it's nice if you actually target past the mob you want with Right on the D-pad you can just hit left to get right back to the one you wanted.
Also, it makes healing very easy on controller also, because if you use Up and Down on the D-pad it will cycle through only your party list. Not as efficient as click-selection but the amount of time you waste, when adept at using a controller, compared to clicking is negligible.