No; Nimoy did well but the scene contributed little ...
As I posted before, it DID contribute something. The scene ends with nuSpock asking how they defeated Khan. Later, when Kirk is dying in the warp core, he tells Spock "It's what you would have done.", and Spock clearly reacts with shock. He *knows* that's what he would have done, because Prime Spock told him he did exactly that!
Was it necessary? Who knows. But it did serve a purpose for the film.
How they defeated Khan in TWOK:
1. hide the ship in a nebula so that the odds will be even
2. recognize that the Reliant's navigation pattern suggests 2-dimensional thinking
3. attack the ship from below and render it defenseless
4. get the ship out of range before the Reliant explodes
JUST HOW would that help nuSpock?
And how did nuSpock know that oldSpock knew Khan?
"Hey bro, do you know a bad guy named Khan?"
"No I don't."
Heck, this makes no sense. Even IF oldSpock knew Khan, the circumstances would have been entirely different (and, d'oh, there indeed were). "How did you defeat him?" Is he a game level boss that can be beaten with a special cheat? "Listen, every time you encounter Khan, your engine will fail, so someone has to sacrifice himself to repair it."
I'd love to see the next conversation between nuSpock and oldSpock.
"So, my young self. How did you defeat Khan? Did you use his lack of 3D navigation experience against him as I suggested?"
"Well, no, I beat the crap out of him. But thanks for the advice."