New this week Continuity mistake: After Mr. Shirley tells Clark he will get a bonus plus twenty percent, Catherine, Rocky, and Ruby Sue cheer and get up from the couch to mingle with the relatives while Rusty and Audrey respond excitedly. There is a close up reaction shot of Clark as he begins falling, then a long shot of Clark falling to the floor as Catherine, Rocky, Ruby Sue, Audrey and Rusty are in their original positions on the couch, calmly watching Clark fall.
Continuity mistake: After Eddie et al arrive at the Griswolds, "Snots" is introduced. When everyone else has gone into the house, Clark is left outside with the dog. A shot shows the dog at Clark's side, and if you look at Clark's sleeve, he's wearing a sweater, but actually has on a windbreaker. At the end of the movie, Clark's wearing the sweater. Apparently the shot was taken of him and the dog, and edited back into the film early on.
Visible crew/equipment: Just before Clark goes down the hill on the saucer sled you see the view down the hill. If you look carefully at the right of the screen you can see two pinkish cables stretch into the distance. These are the pyrotechnics that make the explosions Clark sets off. You can see it clearly on the DVD version, but not too clearly in the VHS one.
Continuity mistake: When Clark is sliding down the hill on the sled, several times you can see fins on the bottom to help whoever was riding it control the direction a little better. When Clark is rubbing the oil on the bottom of the sled before he starts it is completely flat on the bottom.
Continuity mistake: After the tree burns up from Uncle Lewis' stogie, he turns around revealing fire on his back. Right as he is turning, the shot cuts to Clark and back to Lewis. In this new shot, Lewis' hair is different (compare the wigs), indicating the person getting the fire on his back put out is a stunt person.
Other mistake: Another note about Clark's falling through the ceiling and onto his son's bed: Take note of the shot of him in the attic after falling through the ceiling. He's standing on the upper bunk of the bed now, but from the shot in the attic, he's only down to his knees or so. Assuming his home's ceiling joists are 8 inches or so, then the mattress of the upper bunk would have to be no more than, say, 10 inches from the ceiling for that much of him to still be in the attic while standing on the bed. I've never seen a bunk bed whose upper bed gave you less than a foot of space between mattress and ceiling!