Back to the Gleam in Dumbledore's Eyes

[Fortescue]

The highly debated passage below still leaves me with questions:

GoF The Parting of the Ways pg. 696

"He said my blood would make him stronger than if he'd used someone else's," Harry told Dumbledore. "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. But next second, Harry was sure he had imagined it, for when Dumbledore had returned to his seat behind the desk, he looked as old and weary as Harry had ever seen him.
"Very well," he said, sitting down again. "Voldemort has overcome that particular barrier. Harry, continue, please."

So, I would assume this all was part of how Harry survived his final meeting with Voldemort. This particular quote has always confused me as to its deeper significance. Dumbledore surely knew about Voldemort's Horcruxes by this point and he seemed to have a lot more knowledge about Lily's sacrifice and its importance to Harry.

DH King's Cross Pg. 709

"He took my blood," said Harry.

"Precisely!" said Dumbledore. "He took your blood and rebuilt his living body with it! Your blood in his veins, Harry, Lily's protection inside both of you! He tethered you to life while he lives!"

"I live - while he lives? But I thought . . . I thought it was the other way around! I thought we both had to die? Or is it the same thing?"

That quote was a little confusing for me. I can buy the fact that Harry survived because he did not defend himself in the face of death, in his willingness to stop the battle and save his friends, but the highlighted part has me wondering still. The neither can live while the other survives does not fit with any of it.

But the next part gave me back all my faith in Dumbledore that I lost looking into Snape's Penseive memories . . .

DH King's Cross Pg 710

"And you knew this? You knew - all along?"
"I guessed. But my guesses have usually been good," said Dumbledore happily . . .

Thinking of Snape's Penseive memory and how cold and cruel Dumbledore seemed with the knowledge that Harry had to die, it made me feel a little sorry for Snape. According to the passage above, Dumbledore was pretty sure Harry would not have to die, yet he led Snape to believe that Harry did have to die in order to stop Voldemort. And Snape's memory led Harry also to believe that he had to die.

Was that all part of Dumbledore's plan????

DH pg. 707 King's Cross

"Harry." He spread his arms wide, and his hands were both whole and white and undamaged. "You wonderful boy. "You brave, brave man. Let us walk."

So, taking all the quotes into consideration, did Dumbledore know, even three years prior to Harry and Voldemort's final meeting, that Harry would have to be brave enough to face Voldemort wandless and face death in order to defeat Voldemort?

The last quote showed that Harry met Dumbledore's expectations of him, obviously!

I don't now if JKR will ever be pinned down long enough to explain in detail to us "hounds" the answers to all of our questions completely!