Dumbledores lack of surprise

[Inge]

No: HPFGUIDX 93920

PS p15 uk edition.
McGonagall: "..... but how in the name of heaven did Harry Survive?"
"We can only guess," said Dumbledore. We may never know."

PS p216 uk edition.
Harry: "Voldemort said he only killed my mother because she tried to 
stop him killing me. (snip) Why couldn't Quirrel touch me?"
Dumbledore (not hesitating before he answers): "Your mother died to 
save you. If there is one thing Voldemort cannot understand, it is 
love. He didn't realise that love as powerful as your mother's for 
you leaves its own mark. Not a scar, no visible sign... to have been 
loved so deeply, even though the person who loved us is gone, will 
give us some protection for ever (snip)."

So - until Harry tells him that Lily died to protect him, Dumbledore 
had no idea how Harry survived. He couldn't have known either - since 
he was not at Godrics Hollow that night.
What made me wonder is how quickly Dumbledore is to give Harry the 
answer about the 'Love Protection' Lily gave him.
Wouldn't someone like Dumbledore more likely have said: "Ooooh - so 
THAT is why - THAT's how you came out of that attack alive!"
But no  - he doesn't even stop to think before he tells Harry that 
this is the reason he survived - even though Dumbledore him self 
didn't know till then (according to his answer to McGonagall earlier) 
and probably has been wondering what on earth really happened that 
night at Godrics Hollow.
Maybe he knew all along and just lied to Minerva.... ?

Inge