Right from the opening scene, it was obvious that this week's Big Bang Theory would focus on the eternally fluctuating relationship between Leonard and Penny. Can't those two ever make up their minds? At this point they're worse than J.D. and Elliot ever were on Scrubs.
Luckily, audiences had Sheldon to serve as the voice of reason this week, inasmuch as Sheldon is ever capable of being reasonable about any subject. His attempts to smooth over Leonard and Penny's fraying romance were amusing, particularly in his liberal use of geeky metaphors to get his point across. When you love something, you just know it, like with swordfish and hammerhead sharks. Sheldon using the transition from Edward Norton's Hulk to Mark Ruffalo's Hulk to illustrate the point that there are other women for Leonard in the world was surprisingly apt. Maybe life really boils down to a person's search for their Mark Ruffalo.