Episodes like "The Ornithophobia Diffusion" feel like tests. In the case of this week's episode, the writers are testing the boundaries of how antagonistic Penny and Leonard can be with each other and how nonsensical, illogical, and silly Sheldon can be. If you usually like these things, then the episode was probably fine. If not, the episode is painful.
The Leonard and Penny stuff I could live with. Though on the mean side, the plot did explore their relationship which was sorely unexplored when they were actually together. From the way they were acting, they probably won't be getting back together anytime soon.
The Sheldon plot, however, was pretty dumb. Sheldon's supposed to be neurotic genius whose intelligence is often overshadowed by his social awkwardness. Here, he's just neurotic, devoid of any character besides his phobia.