Dumbledore Triumphant: Speculate

[kchuplis]

No: HPFGUIDX 145640

I have been looking for something to follow up Harry's observation when telling 
Dumbledore and Sirius about LV cutting him and using his blood in GoF pg. 696 
Scholastic hardback:

 "He said the protection my - my mother left in me - he'd have it too. And he was 
right - he could touch me without hurting himself, he touched my face."

For a fleeting instant, Harry thought he saw a gleam of something like triumph in 
Dumbledore's eyes. 

___________________

Why would that spark triumph in Dumbledore? And  yet, it seems the sort of clue that 
is often followed up on way later. Any ideas?

kchuplis