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.