Curate, connect, and discover
L: If I do this, and he does this, causing me to do this, then he's definitely Kira. But if he does this instead, then I'll try this, and he reacts like this, THEN he's Kira. But I won't be CERTAIN unless I do this and he responds by doing this OR if that thing I thought he did a while back was actually him doing this to cause me to do this…
Near: Look I don't know if L was certain or not, but frankly I don't give a crap. You're literally the only option by this point. Let's just skip to the end where I win and you shut the heck up already.