No, "that being said" isn't nearly as useless as you make it out to be.
Ordinarily what follows the phrase "that being said" is a concession of some of the implications of the previous statement.
Nick Swisher's BB/K rate has been especially good for the last month.
That being said, his power and run production numbers are down significantly, making him much less valuable over that span than before.
That being said replaces the word "however" or the phrase "In spite of this."
It does carry its own meaning, albeit one derived to some extent by the context.
It still has a place in my writing.