Regarding the Harry/Snape eye contact..

[potioncat]

No: HPFGUIDX 181583

>>Doddie:
So all of these instances I'm wondering, is Snape on a search mission
(to trap the son of James), or is he remembering(Lily)?!?

It also adds an entirely new creepy light on detentions...
Snip
I dunno, I just don't think that Snape is as a successful
Legillimens against Harry as he was towards everyone else(only
because he went searching for Harry's expeiences with Lily...

Potioncat:
IMO, Snape stared into Harry's eyes to get information. He wasn't 
looking for Lily. Before he even knew Harry, Snape had paired Harry 
with James. Remember that he wanted DD to protect Lily, and only 
agreed to protection for her son and husband when DD pushed. Still, I 
don't think he was trying to trap James's son. But I do think Snape's 
opinion of Harry was based on his being James's son.

Legilimency has the same limitations as other forms of human 
communication. Sometimes you see/hear what you expect to see/hear, 
rather than what is really there. It seems to me that Snape develops 
his Legilimency skill over the 7 books, improving as time passes. Do 
we ever see Snape using Legilimency on anyone else in canon? I don't 
particularly remember.


>>Doddie:
Also, I think Snape may have come to some epiphany in HBP when he
heard about Harry's progress in potions!!

Potioncat:
My first reaction was to dispute this. I'm sure Snape didn't think 
Potter was any better at potion making than he had been. But that 
isn't what you mean is it?  You know, Slughorn is the only person I 
can think of who compares Harry to Lily. Could this be the first time 
Snape has had reason to see Harry Lillyson rather than Harry Jameson? 
As much as we sometimes fault Snape and Black for confusing Harry 
with James, it does seem to be a consistent opinion that Harry is 
very much like his father. 


>>Doddie
Alas, I don't like Snape, but I don't think DD did either until
close to 1/2 way through their adult relationship either--Snape's
POA incident when Harry cast the Patronus with a big ol' stag which
reminded Snape about Lily too much!(and he had a couple of
decades)...or in GOF when post dh both DD and Snape seem to be
scratching their heads about who the traitor could possibly be..

Potioncat:
Unless Severus understood that "Prongs" referred to a stag, he 
wouldn't have reason to connect the stag Patronus to James. Snape 
didn't know that James was a Stag Animagus and I don't think he would 
have known what James's Patronus was. If I understand JKR's comment, 
the Patronum charm wasn't taught at Hogwarts. It would have been 
learned afterwards.  

For that matter, how did Severus know that his doe Patronus reflected 
Lily? Because he clearly does know it. Argh! Now I'm going in circles!