Godric's Hollow and the Fidelius Charm again (Was: Apparition & Secrets

[houyhnhnm102]

No: HPFGUIDX 167981

Carol:

> I'm talking about someone who knew the Potters' hiding 
> place *before* the Secret was concealed but was not told 
> the Secret *by the Secret Keeper* *after the Charm had 
> been cast.* I think that person, for example, Lupin or DD, 
> would no longer no what he knew before because that 
> knowledge is now concealed inside the Secret Keeper. 
> Unlike Sirius Black, who knew the Secret but couldn't 
> reveal it, they wouldn't know the Secret because Wormtail 
> hadn't told them. Their knowledge before the Fidelius 
> Charm was cast would be voided by the Fidelius Charm, 
> which requires the SK himself to tell the Secret in 
> order for it to be known.

houyhnhnm:

The aspect of the Fidelius charm that I've never seen 
discussed is how it works to prevent someone who has been 
given the secret but is not the SK from giving it away.

In "Spinner's End", Snape says, "I am not the Secret-Keeper; 
I cannot speak the name of the place."  That implies that 
the constraint works on the sender not the receiver of 
information about the secret.  

"As long as the Secret-Keeper refused to speak, You-Know-Who 
could search the village where James and Lily were staying 
for years and never find them, not even if he had his nose 
pressed up against their sitting room window!", said Flitwick.  
That sounds as if, possibly, even if someone else who knew 
the secret were to divulge it, the information could not 
be received.

Harry speaks the address of the Order's headquarters twice 
out loud when he is using the fireplace in Umbridge's office.  
Was he able to do so only because he was alone?  What 
would have happened if Umbridge had caught him out the 
first time or been a little quicker the second? If she 
had opened the door right at the moment Harry was saying 
"Twelve Grimmauld Place", would Harry have had an automatic 
Silencio kick in, or would Umbridge just not have heard 
anything or maybe heard some noise issuing from Harry's 
mouth but be unable to process any meaning from it?

Is Snape spinning another one for Bella?  When he asks, 
"You understand how the enchantment works, I think?" is 
it an expression of his confidence in the fact that 
she has just shown him that she doesn't?  Not that there 
is really much difference in terms of effect between what 
he says and something like "I could speak the name of the 
place, but none of you would be able to hear it," but why 
not say that?