Tabitha Shepard is NOT a renegade. Really, she's not! (Well, ok, maybe a little.) She didn't push that merc out the window. She let Shiala live and saved the colony on Feros. She told Harrot to let the Quarian set his own prices and even gave the Quarian 1000 credits so he could continue his pilgrimage. She could have picked Morinth over Samara, but she didn't. She didn't let Niftu Cal, the great biotic wind, commit suicide. She even ended up saving the cure data. Ok, ok, so she did let the council die. And yes, she has been known to shoot pontificating Krogan before their speech was done. But it was never the intent that this be a "renegade" playthrough. I have just been role playing her, not focusing on morality points. But it seems like quite a few times when a speech check comes up the only option available is the intimidate one.
And what an experience it has been! Shortest interogation ever?

Toy ships? double

Asari always hide behind behind someone else when a fight appears imminent? (Actually, the dialogue on that one made more sense than the paragon option since it showed Shepard covertly letting Liara know how they should handle Vasir.)
What's really interesting though is how little difference there is between my renegade and paragon scores: Paragon 3.25 bars, Renegade 4.25 bars. And I know it wasn't even that big a difference before Tabitha told off the Admirals since that one option alone netted 32 renegade points. Strarting out with the "ruthless" background, of course, has been a big help with its 200 point renegade bonus (plus it has helped define who Shepard is).
Anyway, I'm glad I got to hear some of this dialogue, even if that was not my intent. I wonder what Liara is going to say about Shepard for her time capsule?