Dumbledmore is ok with it as long as "the end justifies the means."

[vmonte]

No: HPFGUIDX 95270

Carol wrote:
As for Fake!Moody teaching the children to defend themselves, that was
the only way he could make sure that someone else, say, Karkaroff,
didn't ruin his plan by Imperioing Harry to keep him from winning the
tournament. It's another case of evil will (the intent to harm) having
fortunate consequences (just as good intentions sometimes have evil
consequences, Harry's refusal to use Sirius's mirror and his
prevention of PP's murder being the examples that jump immediately to
my mind). In any case, the Protego doesn't involve a deliberate effort
by Harry, who also accidentally casts a stinging hex that leaves a
welt on Snape's arm. It's reflexive magic like releasing the snake at
the zoo rather than an act of will. 

vmonte responds:
I'm pretty sure Moody didn't teach Harry how to throw off the curse 
because he thought that Karkaroff would Imperio Harry and ruin his 
evil plan. We don't really know why Moody taught Harry how to protect 
himself.  He may have been testing Harry, to check his strength as a 
wizard; just like I believe (and I'm sure you do not agree) that 
Snape was testing Harry when he whispered into Draco's ear 
Serpentsorcia (and yes I know that we did not hear what he whispered 
into Draco's ear).  

We are all making guesses here. Right?!  
Harry's strength is not in his extra ordinary knowledge of magic but 
that his talent is instinctive. I wouldn't say that the stinging hex 
was an accident but I would say that it's (as you say) more 
of "reflexive magic."  Harry has natural talent! That is not 
something you can teach someone, either you have it or you don't.  

Moody may have been testing Harry because he was curious to see what 
all the fuss was about.   

vmonte