Should I write "that being said" (vs. "that's been said" or "Having said that")?

I often write what "sounds" right (being not a native English speaker/writer), and I believe the expression "that being said" to be fairly common, as opposed to a more complete form like "that's been said" or "Having said that".

In doubt, I turn to google fight, which seems to confirm the common usage. (not exactly the right reference, I know.)

Yet, I don't think that "that being said" is correct, especially in writing. "That said" is even more common. Is it also acceptable in writing?

What expression would you use in formal writing? (Not too formal though: like a technical forum)

Solution 1:

Both "that said" and "that being said" are common (possibly too common) and perfectly grammatical, and sufficiently formal as well. "Having said that" is also correct, but to be correct the subject in what follows must be whoever said that (usually "I"). For instance, you can say:

• Roses are usually red. That [being] said, they are also…

But you'd have to say:

• I like turtles. Having said that, I will now proceed to show…

That said, if you don't follow it up with "I", many people wouldn't notice anything amiss these days.

"That's been said" is a full sentence (edit: complete clause), and it only means "That has been said". Full stop. It cannot be used to introduce the rest of the sentence in the same manner.

Solution 2:

To my ear, "that's been said" is actually wrong if used in this context. The other two, "that being said" and "having said that" are normal; I would say they are somewhat fossilized expressions. However, they aren't ungrammatical. For instance:

1) The car being washed, Hugo went home. (somewhat archaic sounding, but I think fine)

2) Having washed the car, Hugo went home. (perfect)

"That's been said" will sound distinctly odd if used in the same way, probably just because it is not a recognized idiom.