Other mistake: When Harry spits baby food on the baby (the camera lens in actuality) in retaliation for the baby spitting food on him and Tommy, Joseph Gordon-Levitt breaks character and laughs uncontrollably and looks at and gestures to off-screen crew members a couple times. (00:06:25)
Continuity mistake: When Jennifer comes into work the next day after her dinner date with Dick, her face is covered in hives from an allergic reaction. Later when Dick interrupts her choral group, the hives on her face have disappeared. She and Dick are wearing the same clothes in both scenes, so she couldn't have overcome such a reaction in such a short amount of time. (00:12:30 - 00:15:00)
Continuity mistake: In 1-2: "Post Nasal Dick", Harry has a dream about Martha Stewart. But in this episode they panic because they dream and have nightmares and don't know what they are. Shouldn't Harry have panicked when he dreamed about Martha Stewart?
Continuity mistake: When Ms. Dubcek is showing the Solomons the attic apartment in the pilot episode, they enter (and she later exits) through what is Dick's bedroom in all subsequent episodes. Additionally the staircase at the back of the living room that serves as an entry point is completely missing.
Other mistake: When Dick is trying to get into the jewelry store, the clerk keeps trying to buzz him in. When that doesn't work because Dick doesn't understand to wait for the buzzer to finish before he tries opening the door, the clerk goes over to the door and unlocks the deadbolt and opens the door for him. If the door was locked by a deadbolt, then a buzzer wouldn't really do anything to unlock the door. (00:14:05 - 00:15:00)
Continuity mistake: Dick's plot in this episode is that he learns about the concept of tipping. However, the season 3 episode "Eleven Angry Men and One Dick" showed that Dick was already familiar with the concept of tipping when he tipped a bailiff during a jury selection process.
Revealing mistake: In the scene with www.planetsolomon.com, you can see that it is a pre-filmed video (not a live stream as he said), as it has a time slider and play/pause controls etc. (00:13:05 - 00:13:45)
Other mistake: When Dick is up in the tree fort, the aliens are looking at him through their hand binoculars, but the image is taken from the same height as Dick. However, since he is higher than they are, they would be seeing him at an angle. The view as seen would be impossible unless they were at the same height as he was.
Other mistake: While talking to his therapist, Dick tells her that one of the mishaps that he caused in his relationship with Mary was showing up to a fundraiser naked. While true, this doesn't happen until Episode 13 (Rutherford Beauty) - two episodes later. This was due to the fact that most of Season 5 was aired out of production order.