You've never done a proper BR then.
A BR will increase DPS by a nice amount, granted your PT mates who will be participating in it cooperate and stack in a timely manner. I take it you haven't looked at the debuffs granted via BR, nor the increased damage output from a stack of 3+. If everyone stacks up in an efficient manner, you'll be back to attacking/healing/voking/etc in a matter of seconds.

If anything, BRs only achieve one thing: to further enable the player to watch tv or talk on MSN while playing. Its a system designed to pay less attention to what you're doing in the actual game.
Yeah, because auto attack won't do that at all. Again, cooperate with each other and you will pop a BR in less than a few seconds and be back to whatever you decide to do in battle.