The Irma/Eileen Theory & Snape's Return/Teaching timeline

[zgirnius]

No: HPFGUIDX 164193

 
> Jen:
> First back to the idea that Snape's remorse was a separate event 
from 
> his job at Hogwarts, likely by a couple of months. 

zgirnius;
I find this to be suggested as well by Dummbledore's testimony in 
GoF. How could Snape spy 'at great personal risk' if he 
only 'returned' just in time to start teaching at Hogwarts? Who was 
he spying on? If on the other hand Snape 'returned' at some point 
before he started teaching, this comment could be in reference to his 
activities before he started teaching, spying from within the Death 
Eater camp, which makes more sense to me.

Jen: 
> Moving now to the hole in Voldemort's order to Snape.  I found it 
> curious Voldemort ordered Snape to get the job when Voldemort and 
> Dumbledore both knew Snape was the DE who had turned over the 
> prophecy to Voldemort--why exactly did LV think Dumbledore would 
> agree to this?  My answer is...he didn't think Dumbledore would 
> agree.  It was an impossible task, just like Draco killing 
> Dumbledore, and Snape was sent in part as punishment for not 
> delivering the entire prophecy and thus making Voldemort's job 
harder 
> when the Potters escaped him (in Voldemort's mind).  The motivation 
> he offered to Snape for completing this impossible task?  Same as 
> Draco's, 'I'll kill your mum, Eileen the Muggle lover'.

zgirnius:
This seems plausible to me. Minus Eileen, it is the story I've come 
up with for myself from the clues we have in Dumbledore's statements 
from HBP and GoF, Fudge statements in PoA, and Snape's statements in 
HBP (Spinner's End). Though, to make a correction, we have no 
indication Dumbledore knew 'officially' that Snape was a Death Eater. 
He might have suspected it after Voldemort's actions tipped him off 
to the fact that Voldemort knew the prophecy. Though even then, it 
could just indicate that Snape told the story to the wrong friends, 
friends canon suggests he had.

Of course, once Snape approached Dumbledore, I presume he would have 
made a clean breast of that, but Voldemort would (at this point) not 
know that Snape had confessed to Dumbledore.

And yes, if Dumbledore trusted in the genuineness of Snape's remorse, 
I think he would try to help him out of a tight spot such as the one 
you describe (Voldemort ordering him to get a job at Hogwarts). From 
a purely practical standpoint, Snape might retain some usefulness as 
a double agent at school, either by spreading misinformation, or 
through what he could learn from his (presumably less frequent) 
contacts with other DEs. Dead, he wouldn't.