So, yes. Damon says it's inevitable that Elena will kill. Stefan, meanwhile, is trying to keep our girl from making all the mistakes he's made. Damon favors a "rip off the bandage" approach. Stefan favors the control freak approach. Oh, these boys. Sometimes, their scenes must write themselves. I mean that in a good way. Everything about this argument between Damon and Stefan has been set up over the past three seasons. It would be impossible for them to not have this argument.
Damon doesn't want to see Elena deny her nature and turn into some Ripper freak. Stefan doesn't want to see Elena indulge her nature and turn into some Ripper freak. He also doesn't want to see her turn into a Damon, though. Damon knows this and calls out his brother on that very fact. The one thing Damon doesn't do here? He doesn't confess that he doesn't want Elena to be like him, either. He doesn't say it, and probably couldn't admit it to himself, but what he wants is for her to be just corrupt enough that Stefan falls out of love with her -- corrupt enough that Damon will be worthy of her without all this bothersome growth and change.
During the argument, Stefan notes that Elena's compassion is her Achilles' heel, and because she's a baby vamp, all of her feelings are magnified right now. We cut to a scene of Stefan and Elena hunting a baby deer. Back at Mossy Manse, Damon says, "You'd better hope she's not a fan of Bambi."
In the woods, Stefan tells Elena to close her eyes and then rushes at the fawn. At Mossy Manse, Damon notes that baby vamps need blood -- from the vein. Stefan blahs about killing people. Damon blahs back about how the bunny diet creates Rippers. In the woods, we see Elena feed on the deer. When she rises up from feeding, blood drips down her face. It's not as gross as all the blood vomit in this episode, but it's enough to activate my gag reflex.
At Mossy Manse, Stefan frets that if Elena does something awful, the pain and guilt might make her switch off her humanity. Damon continues with his it's inevitable argument. "She can't learn to control the bloodlust if she's never experienced the bloodlust. It's a cheat. It's like giving a kid a calculator before they know math."