Locke (the fake one) steals a line from Locke (the real one). Weird!

I thought the strangest moment in “The Substitute” was when fake Locke (aka Flocke, notLocke, unLocke, and the Locke-ness Monster) chases after the blond kid. Fake Locke falls (not unlike the way that Real Sideways Locke falls), and the kid stands over him, and says “You know the rules. You can’t kill him.”

"You know the rules. You can't kill him."

Then fake Locke says, “Don’t tell me what I can’t do.”

The kid shakes his head and walks away.

Then fake Locke points his finger and yells, loudly: “Dont tell me what I can’t do!”

"Don't tell me what I can't do!!"

So why does fake Locke sound exactly like real Locke here? Why is he repeating real Locke’s most famous signature line?

We’ve already seen leakage into the Sideways world. Could there also be leakage into the Island world?  Is that what we saw in this scene?

Or is something else going on?

I listed the possibilities that occurred to me in the poll below. What do you think? Do you have any other ideas?

Here’s the clip:

Screencaps from lost-media.com.