Continuity mistake: After Bart has caused the avalanche in Alaska, the animals help Marge and Homer have a special moment, and when the couple join hands note the large window beside the TV, which just vanishes in the following shots of that bedroom.
Continuity mistake: When Homer drives toward the small Alaskan booth, on the road there is a single line of broken yellow lines leading to the booth, but when Homer hugs the booth guy the road is visible and there are double lines consisting of a solid line and broken lines.
Continuity mistake: When Homer is driving toward the small Alaskan booth, right beside the booth there is a tall flagpole with two raised flags, but when they leave the flagpole has vanished, though it should be seen in this shot since it's on the same little 'island' as the booth. Also note that the snow on the booth and island has vanished.
Continuity mistake: When Russ Cargill shows the President the surveillance footage of domed Springfield, the President's desk is only a few feet away from the fireplace, which is absurdly closer than in any other shots.
Continuity mistake: When Bart walks into Krusty Burger, in the overhead shot the trash receptacle that's beside the door has a plain, flat top with nothing atop it. However, in the following shots the top of that trash receptacle has changed, it now has two raised side lips, and there are also two trays on it. Its height compared to the window behind it drastically changes as well. (00:13:30)
Continuity mistake: When Bart walks into Krusty Burger, in the overhead shot we see Ned and his sons sitting on stools with bases attached to the floor. In the next close-up, Rod and Todd Flanders' stools are in different positions - note the checkered floor. (00:13:30)
Continuity mistake: When Bart walks into Krusty Burger, Ned holds up a pair of blue pants and specifically tells Bart, "If you need pants, I carry an extra pair. You know how boys are, always praying through the knees," but after the commercial is filmed, when the pig stands on its hind legs with Homer, we see Bart's leg under the table and he's wearing shorts, not pants. (00:13:40)
Continuity mistake: Right before Homer yells out of his bedroom window, when the shot moves forward, passing through the large angry mob, we see the mob walking down the street which is perpendicular to the front of the Simpson house (not the street in front, that runs parallel to his house). The problem is that after the dome was placed, when Homer screamed in the backyard, there was an overhead shot that zoomed out and we saw there are homes across the street from his house, no perpendicular street.
Continuity mistake: After the dome is placed, when the Simpson family runs out the back door of the house and Homer shouts, there is only one window on the second floor, above the back door. There should be two windows. The light fixture on the wall beside the door is also gone in some shots. (00:27:40)
Continuity mistake: After Marge has brought Homer to see Maggie outside the dome, and then he thinks he's out of the dome, when he runs back into the house the water spigot attached to the house has vanished. (00:30:50)
Continuity mistake: When Marge brings Homer to see Maggie outside the dome, but she's not there, he soon starts cheering and in the dome's reflection he raises his right arm which means it's his left arm that is actually raised, but when it cuts to Marge and Homer (in the view from outside the dome) it's his right arm that's raised in a cheer. (00:31:05)
Continuity mistake: When Marge sits on the back porch swing knitting 'dome sweet dome' and sees Maggie outside the dome, she runs inside to get Homer. The back door is right behind her and it's a solid door, with the round window missing, though the window does reappear. (00:30:35)
Continuity mistake: After the book knocks over the AA meeting's coffee machine, when the group of people run out of the church, the ground in front of its doors is flat and leads straight to the walkway. Additionally, there is a second large area of grass between the sidewalk and the street, and the large cross at the front is gone. However, in previous and following shots there are stairs at the front of the church, and the area of grass only between the church and sidewalk/street.
Continuity mistake: With the second set of options spread across the desk, when Cargill starts manipulating the President's option choice, there is a blank wall to the President's left (the wall faces the viewers). Also note that in this shot the table behind the President (with framed photos) is gone. When Cargill walks away from the President holding 'option 4', that blank wall now has a built-in bookcase, a table and chair.
Continuity mistake: There is a blue Presidential flag behind the President, with windows on both sides of that blue flag, but after viewing the security camera footage of domed Springfield, the window on the far end has become a solid wall. That window returns when Cargill influences the President's choice of options.
Continuity mistake: When Russ Cargill spreads the second set of the five options across the President's desk, the Oval Office background is actually backwards - note the ship painting over the fireplace and pictures on the wall. The background keeps flipping between being backwards and the correct way until 'option 4' is chosen.
Continuity mistake: After Russ Cargill goes through the eye security system, in the overhead shot as he enters the Oval Office, we see the Seal of the President (on the rug) centered between the two couches, and there are two red chairs behind each of the couches. However, when Cargill holds up the tank with the mutated squirrel, the large round Seal is off to the side of the couches and one of the chairs is gone from behind the couch. (00:24:50)
Continuity mistake: When Russ Cargill holds up the tank with the mutated squirrel to the eye security system on the wall, there is a square piece under the handle to secure it to the top. However, when Cargill holds the tank up to the President that square has vanished and it's just the handle. Then when the President is face-to-face with it, a bar has appeared between the two sides of the handle. (00:24:50)
Continuity mistake: When Lou shoots at the skateboard Bart goes flying in the air, and in the next shot (before he flies past the truck's windshield) we see Krusty Burger across the street (note the triple window and post), and there is a tall, long bush between the street and Krusty Burger. That bush vanishes in the following shots. (00:12:50)
Continuity mistake: When Lou scrapes Bart off Krusty Burger's triple window, Lou is pushing Bart forward in front of him, so Bart should have fallen on the ground somewhere to the front/side of Lou. However, in the next shot Bart is lying on the ground about 20-30 ft behind where Lou had been standing, on the grass that's in front of the door. (00:12:55)
Answer: I believe the joke is supposed to be that the way Texans speak is a language all its own.
Damian Torres