Plot hole: As the guys are checking out the vacant house inside, they are surprised to see it has a pool. However the problem with this is its right next to the driveway in the front of the house, in the open with no fence in front of the driveway so it would provide a clear look through from the alley. As they state they never noticed it in 18 years living there, yet walking up and down the alley it's a bit hard to imagine being that open and they never saw it. Even the final shot (aerial shot) at the end of the episode we see it was far too obvious for them to have never seen in that space of time.
Suggested correction: However, just because something's hard to believe, it doesn't mean it's impossible. As unlikely as it seems, they didn't notice (or maybe they did and simply forgot about it).
Trivia: One of the show's creators made a cartoon about a retarded pig. Boomhauer's voice is based on the voice of an angry viewer who called when he was offended by the cartoon.
Suggested correction: The person was actually complaining about "Beavis and Butthead." For some reason, they called the show "Porky's Butthole."
Factual error: When Nate goes to see Hank to show the incriminating photos of Bobby watering the lawn you can see Nate's car has orange tinting on his front headlight. Front headlights cannot contain any color tinting and must be clear. The car is an expensive looking car. I doubt he wanted to change the tinting of it either.
Suggested correction: Something being illegal doesn't mean someone can't do it. Like drink-driving. He's just taking a risk that he won't get caught.
Other mistake: At the prison, Bill meets Alicia, the same woman who gave Leanne a ride to the Hill house in Season Two ("Leanne's Saga"). Same voice, tattoo on the arm, and general appearance. Alicia tells him that she was in prison for killing her boyfriend. So it's odd that she was free in Season Two. Most likely, a sentence for homicide or manslaughter would be at least five years, and that much time has not passed. Otherwise, Bobby, Connie, and Joseph would be in their late teens.
Suggested correction: It's likely that Alicia never killed any boyfriend. She senses that Bill is the type of guy who she can probably push around, so she wants to intimidate him by claiming that she was in prison for murder.
Plot hole: Amazing that neither Hank's mother nor father ever saw the bandage on the back of his head, peeled it off, and would discover his tattoo.
Suggested correction: And yet they didn't. Just because something's amazing doesn't make it a plot hole.
Character mistake: When Peggy is meeting Lucky's sister at Luanne's baby shower, she mentions that she lives across the street. However, the baby shower is taking place at Peggy's house, as evidenced by the layout of the house and the wallpaper.
Suggested correction: Peggy does live right across the street from Luanne, which is what she is saying. Myrna knows she was at Peggy's house. Since Myrna never met Luanne, she might not know where Luanne and Lucky live.
