Just like the other Robin.

She was honestly tempted to ask if the two of them were related.

"And I don't know you, either. So I guess that makes us even." Straightforward and to-the-point, but with a hint of playful tone behind the otherwise truthful statement. "Though I'd be more than a little impressed if you actually could figure out what I can do just by looking at me. Most people at least try to ask a few questions first."