Why does Dumbledore make Snape DADA teacher?

[justcarol67]

No: HPFGUIDX 158444

Steve wrote:
> <snip> To the last part of Carol's statement, I will only partly
> agree. I think it is critical at this time, now that 
> Voldemort is truly back and the DE's are active, to have
> a REAL DADA teacher, one who knows his stuff. But I don't
> think Dumbledore was holding Snape in reserve 
> intentionally. I think he simply ran out of options and
> had to pick the only available and qualified candidate. <snip>
> 
> As to the other ways in which Dumbledore made use of 
> Snape, Snape would have been available to perform those 
> functions not matter what position he held. So, 
> Dumbledore really doesn't gain anything in terms of 
> secondary aspects from given Snape the job.

Carol responds:
I can't prove it, of course, but I think Dumbledore knew that at some
point he would have to make Snape the DADA teacher, if only because he
would be the only available candidate, and he didn't want to waste
him, or lose his services too early, by giving him the position before
it was absolutely necessary.

And I would argue that making potions as needed (Mandrake solution,
Wolfsbane Potion, Veritaserum) was part of Snape's duties as Potions
Master, whereas removing the curse from the necklace and saving Katie
were part of his duties as DADA teacher. If someone else had the
position, that would have been their job, not Snape's, just as it was
Lockhart's job to go after the monster in the Chamber of Secrets (as
he had been bragging that he would do all year). When Lockhart says
that he'll brew the Mandrake Restorative Potion, Snape responds
coldly, "I believe I am the Potions Master at this school." At the end
of the year, when Ginny is taken into the Chamber of Secrets, Snape
tells him that his moment has come at last. No one questions that it's
Lockhart's job to deal with the monster (though they doubt his ability
to do it): all the other teachers side with Snape. And Harry and Ron,
overhearing the conversation, decide to go to Lockhart for help, and
when he tries to refuse, Harry says, "But you're the Defense against
the Dark Arts teacher! You can't go now! Not with all the Dark stuff
going on here!"

It seems to me that, just as it's Sprout's job in that book to grow
the mandrakes and Pomfrey's to administer the potion, it's Snape's job
to make the potion and Lockhart's to deal with the "Dark stuff." In
HBP, Dumbledore knows there's going to be even more "Dark stuff" to
deal with, especially if he and Harry manage to find a Horcrux, and he
wants someone familiar with the Dark Arts in the position of DADA
teacher. Imagine if there had been another DADA teacher and McGonagall
had sent Filch to Snape, the Potions master, with the necklace. Don't
you think the DADA teacher would have stepped in and insisted it was
his job? And Snape uses Lupin's position as DADA instructor as an
excuse to consult with him about the Marauder's without revealing that
Lupin is one of the makers of the map (Dark magic is "supposed to be
your area of expertise"). In HBP, Dark Magic/DADA is Snape's area of
expertise, and Potions is left to Slughorn (unless Snape wants a
student to sort rotten flobberworms from good ones for detention).

At least we agree that, as far as teaching itself goes, Severus Snape
is the best man for the job.

Carol, wishing that the position hadn't been cursed and Snape could
have taught DADA from the moment he first applied