The "Big Bang Theory" season 8, episode 18 tackled two lingering issues from the recent weeks' episodes. Together with the farewell dinner, the fallout of Sheldon and Leonard's collaborative paper was, once again, brought up. It was rather obvious that the show was coming up with another stage for a new rift.
Leonard might have a brilliant idea; however, it was Sheldon, who did all of the needed leg work in manifesting the idea's jist into a complete theory that is backed up with mathematical solutions. The two, eventually, collided when it came to who deserved the paper's credit more.
It was refreshing to see Sheldon concerned about the article's effect on his friend. Amy had to translate the issue into a term he would better understand, but when it kicked it, he immediately showed an unusual intensity of empathy.
Then the two characters became more snippy and bitter. The empathy that Sheldon once felt was replaced by his smug superiority. Leonard, on the other hand, did all that he could to respond with all kinds of passive-aggressive resentment.
This conflict has made the episode lose its humor. Worse, it has made Leonard and Sheldon come off poorly. Both were unlikable when the dinner scene rolled out. The feud, most especially, seemed petty as it coincides with their friend's difficult life stage.
The two characters stopped fighting because their energy was eaten up by so much food to consume. These two still have a lot of lingering issues to resolve, especially that Leonard is drifting away from Sheldon and more into Penny.