Continuity mistake: In the beginning, after Dennis Quaid has been beaten up, the pins on his jacket are pinned, then hanging askew, then pinned again. (00:03:55)
Continuity mistake: When Jack is having a seizure at his job he stuff some aspirin in his mouth. When the manager says "He is spaced out." it cuts to the girl saying "I'll handle this.". At that point Jack has got two aspirin hanging out of his mouth. It cuts and the aspirins are gone. (00:30:20)
Continuity mistake: Inside the truck when Jack is freezing his head is shaking. But from Tuck's view, inside Jack, he is not shaking at all. (01:00:00)
Continuity mistake: Just after the scene where Jack Putter gets tazed by Lydia Maxwell in the restaurant, Mr. Igoe initially hauls the unconscious Putter over his left shoulder. In the following shot you'll notice that when he exits through the back door, he's carrying Putter over the right shoulder. This mistake was pointed out by the director (Joe Dante) himself on the commentary track of the DVD version. (00:58:10)
Continuity mistake: We see Jack looking in a mirror in order to show himself to Tuck, but when he turns away, the picture on Tuck's monitor is still focused on the mirror. (00:52:50)
Continuity mistake: In a scene right before Jack jumps into the car from the truck we can see Lydia grab the back of his ankle. When it cuts the way she holds his ankle changes. (01:04:20)
Continuity mistake: When Pete and Dr. Niles are in the car discussing the project, the background keeps changing depending on the camera angle. They're suppose to be stuck in traffic, driving near a giant hillside. But in some angles there's no cars next to them and it's wide open space with no sign of the hill. And the cars around them change. (00:11:00 - 00:12:00)
Answer: Probably, but most likely it's because Jack's pod is fragile and wouldn't survive the shock wave heartbeats. The pod is experimental and built for scientific observation, not battle.