This show just does it again and again, that the element of surprise is not there anymore. A lot of dimensions of Jim Parsons has been explored this season, and he has just ripped it off. Here he tries to help Sheldon cement his relationship with Stephanie, for the reason that he considers her at par with his intellectual standards.
Its also interesting to look at the way, he develops a chemistry with any new character that already exists or comes into the show. We also, see Wolowitz and Koothrapali underutilized this episode. For most part, they weren't even there on the screen. The Sheldon-Penny combo also seems to work pretty darn good. Its also good to see Leonard pitching in with some good lines. I don't see the problem in this show being Sheldon-centric. If the show spirals down, it wouldn't be because of this strategy, rather it would be because, you've run out of ideas. A super-comedy week from CBS.