Due to a horseback riding accident where she broke one of her legs, Kaley Cuoco is listed as credit-only in this episode.
This episode and the previous one, The Desperation Emanation (2010), are the only episodes in which Penny doesn't appear, due to Kaley Cuoco's horseback riding accident where she broke her leg.
The only episode where none of the 3 main women (Amy, Penny and Bernadette) appear
"Lucky Baldwin's," the Irish pub that Sheldon references, is actually a real pub located in Pasadena, CA. The address is 17 S Raymond Ave, Pasadena, CA 91105.
Like in The Loobenfeld Decay (2008) and The Bad Fish Paradigm (2008), Sheldon is unwillingly burdened with a secret that he cannot keep due to his constitutional incapability of deception. Just like he did in 'The Loobenfeld Decay', he conceives of an extremely exaggerated and complicated lie to cover for Leonard.