Why was Snape teaching DADA?

[nobodysrib]

No: HPFGUIDX 135969

anuja:
1.because Dumbledore finally tusts him so much that he thinks it wont
do any harm
2.because he cant (yet again)find a DADA teacher but knows he can find 
 another one for potions.so after getting a new teacher for potions he
had no choice but to let Snape teach DADA?
3.or because he always intended to get the memory from Slughorn and so
needed him at Hogwarts?

Tammy:
4. Snape told Dumbledore about the Unbreakable Vow, that bonded him to
either help Draco kill Dumbledore, kill Dumbledore himself, or to die.
Seeing as how Dumbledore knows Snape will be dead or gone by the end
of the year (I agree with the
Dumbledore-made-Snape-kill-him-to-get-in-with-Voldemort camp) and
therefore granted Snape's last wish - to teach DADA. It shows LV that
Dumbledore trusts Snape completely at last (meaning Snape has done his
job well), and gets Sluggy to Hogwarts to teach the last memory.

<my turn>
nobody's rib:
5. Dumbledore had reasons to mildly distrust Snape, and Dumbledore was
willing to give Snape DADA to test his hunch.  

explanation: Better to see if Snape's on LV's side, the Order's side,
or just-plain-Snape's side sooner rather than later, and especially
under the somewhat controlled situation in Hogwarts.  Not to mention
that we're at war, lives are at stake, the Order has been betrayed
before, and now is the time for action.  It's all about choices, and
Dumbledore might have been forcing walk-the-fence!Snape to choose a
side, showing his true colors.  

[Dumbledore not trust Snape completely?  But he always *says*... BUT,
what about hindsight such as Snape's tutoring Harry wasn't the best
idea. Not to mention, how much does Dumbledore *really* trust Snape --
not just *say* he trusts Snape to perhaps help Snape-dislikers (such
as the Marauders) trust Snape and better unite houses, or perpetuate
the appearance of doubleagent!Snape -- if he's spent years mistrusting
Snape's willpower if surrounded by DADA/DA?  How much do you really
trust a dry-alcoholic if you never allow him/her near a bottle of booze?]

Agreeing with Tammy, I also find
Dumbledore-made-Snape-kill-him-to-get-in-with-Voldemort camp
interesting.  I also appreciate JKR creating a possible double red
herring.  SS: We think Snape's a bad guy, but HRH's focus on this
points us away from Quirrel.  (Fool me once, shame on me.)  Now we
think Snape's not purely on LV's side, and Dumbledore and the Order's
focus in this (plus our, and part of HRH's trust in their opinion)
points us to anyone but Snape -- when Snape was a bad guy all along. 
(Fool me twice...)

My favorite (current) thoughts about Snape involve the words of the
Unbreakable Vow.  (I hope I'm not covering old news.)  Whether acting
as a secret agent for either side or a double agent on only his own
side, did he have a choice but to agree to the vow?  I can't think of
anyway he could have gotten out of it without raising suspicion.  PLUS
(and this is my favorite part) consider the wording of the vow.  The
first two parts, using the exact same wording but with different
interpretation) were things he could have already have intended to do
for Dumbledore or for his own best interests (1. watch over Draco as
he attempts LV's plan, and 2. to the best of his ability, prevent
Draco from harm).  

As for the third part of the Vow, there's Snape's pause...  "should it
prove necessary... if it seems Draco will fail... <snip> will you
carry out the deed that the Dark Lord had ordered Draco to perform?" 
I see two things here:  (1) Snape (as a secret or double agent) has no
choice but to break his cover (not a good idea, especially in the
presence of LV-supporters) or go along with it, knowing Dumbledore
will deem the sacrifice necessary for the greater good (even if
Snape's only concerned with Dumbledore's opinion to maintain
double-agent status); or (2) Snape infiltrates Narcissa's mind in
choosing the wording for part three.  There's so many caveats in the
phrasing!  "should it *prove* *necessary*", "if it *seems* Draco
*will* *fail*"...  Not to ask for the definition of "is", what would
be *proof*; when would it be *necessary*; what does *seems* entail;
why use the future tense *will*; what exactly would it mean to 
*fail*?...  Who gets to define these concepts?  

Throughout HBP, doesn't it seem there's proof that Draco is failing
and Snape reprimands him for making choices that will lead to failure?
 And doesn't that umbrella term "necessary" put the whole of part
three up for personal translation?  In this light, does this
Unbreakable Vow really mean anything?  Is it really possible for Snape
to break it?

(or is this setting the stage for a triple red herring??  augh!)

CASSODMAC-Y!!  
(Can Anything Snape Says or Does Mean Anything Concrete -- Yet?)


-- nobody's rib, who loves Snape theorizing yet wonders if doing so
blinds her to more important clues or connections