In Kazuo Ishiguro's The Remains of the Day, is there a difference between Stevens' idea of dignity and that of greatness?

Stevens’ ideas of dignity and greatness are connected, both qualities relying on each other, yet distinct in their presentation. Stevens discusses at length what it is that makes a great butler. He summarizes it using his father’s words: Dignity in keeping with the position. No matter what, a butler must keep his dignity strong, letting no emotion or personal opinion be visible to his employer. The stereotypical British “stiff upper lip” or restraint is synonymous with Stevens’ opinion of dignity. Therefore, dignity leads to greatness.
Greatness is the quality that Stevens attempts to show in two characters: Stevens himself and Lord Darlington. Having defined greatness, Stevens tries to show himself in this light. During many times of awkwardness or tragedy, Stevens shows restraint, though at times his feelings are obvious, such as the death of his father. However, he never admits to the trouble, merely saying that he is tired.
As for Lord Darlington, Stevens wants to present his employer by the best interpretation of his actions before World War II, in which Lord Darlington was a Nazi sympathizer. Stevens views his employer’s actions as coming from the best of intentions and an honorable heart, but afterward he is considered a traitor. However, Stevens’ own greatness is tied to that of Lord Darlington. When it is clear that Lord Darlington is not a great man, Stevens’ own dignity is shattered, evidence that he has wasted his life serving a man who is less than honorable. While he has tried to convince the reader throughout the novel that both he and Lord Darlington have some measure of greatness by their dignity, he at last comes to admit that neither one does, both having pledged their support to someone who is not what he seemed to be. Stevens doubts that he can lay claim to either one of these qualities, dignity or greatness,  since Lord Darlington has been discredited in each.