I feel compelled to explain the reference to the dog. Think of a dark room, a "significant other", and a case of mistaken identity. The expression originally meant to do something that seemed right at the time but that turned out to be terribly wrong. Now, it just means to make a serious mistake...
Slang by its nature tends to be limited to a certain group. The size of the group varies from a few people or a profession (then we call it "jargon") to a country or beyond, of course. But as some other posters have pointed out here, different countries have very different slang, and although you're speaking the same language as someone else, you can totally fail to communicate. For example, in America, if I say "He's really p i s s e d", it means he's quite angry. In Britain, the same, exact words mean the guy is quite drunk. Few in America know what a Brit means when he says he's "taking the p i s s" which has several meanings, but often means you're mocking someone or you're just joking and not serious. Also few Americans know what "telling porkies" means (to tell lies), but those expressions are common in England and probably other former colonies. Slang can be very colorful and descriptive, but it can sure be confusing, too.
What seems to have been overlooked in the discussion up until now is the fact that PHB, in his attempt to use office jargon/slang to indicate a job poorly done, has mixed his metaphors. Asok's comments in the third frame clearly show that.
1) PHB used "choke the pooch" which is somewhere between "screwed the pooch" and "choked the chicken". Although both have a sexual reference, one is literal and one is inferred.
- "Screwed the pooch" means a job poorly done or left undone.
- "Choked the chicken" is a reference to self-gratification.
2) It would seem that Asok's research led him to a definition leaning more towards the meaning of "Choked the chicken" - hence his guilty disposition in the third frame. I think we can all safely assume that Asok gets no action and has frequently had to "pull the goalie".