First, as long as you do not fail the persuading check you can repeat for ever. Second, you can gain infinate light or dark side points as you wish.

> "What can you tell me about Datooine?"
> "What do you know of the ruins?"
> "Tell me about how the Enclave came to be ruined."
> "Sith invasion?"

This brings the memory overflow and the reset.

> "[Computer] Droid, run a self diagnostic and report."
> "[Repair] Fix the droid's memory unit."

This brings the old man running over asking if the droid called you a Jedi.

> "No, you must be mistaken."

Now you can persuade or force persuade (ends conversation)

> "[Persuade] The droid is obviously malfunctioning. Do i look like a Jedi?"

If you can succed you get more conversation options:

> "Why do you hate the Jedi?" - old man laughs at you
> "But the Jedi are the protectors of common folk like yourself." - LSP
> "Yes. I hate the Jedi too." - DSP
> "I'll be going now" - nothing

Now that the conversation is over, you can talk to the droid again and repeat until either you get bored or fail the persuade check.