Factual error: The commercial airplane that Rogue is piggy-backing to Muir Island has no overhead storage bins. Just a shelf running the length of the cabin with luggage stacked on top, which is not something that the FAA or any other national aviation authority would permit. (00:09:20)
Other mistake: When Rogue is hovering above Muir Island, she pulls out a book to confirm she's in the right place, and the picture of Muir Island in her book shows it to have three smaller islands on its south side. When she lowers the book to look at the actual island, only the large island shown on the southwest side in the book is there. She's only hovering a few hundred feet above the island, so even though the other two islands were small, they should still be visible. (00:09:48)
Other mistake: When Rogue begins flying towards Cable after disarming him, she is only about 30 feet away from him. As she is flying towards him, he takes the time to pull a plasma grenade from his belt, pull out the pin with his mouth, and then throw it at her. In the time it took him to do all of that and given the speed at which Rogue was flying towards him, she should reach him well before he could throw the grenade at her. (00:18:05)
Plot hole: Towards the end of this episode, Jean Grey nearly falls to her death when a concussion blast from Cable's gun knocks her off a cliff, only for her to be saved at the last moment by Rogue. Apparently Jean Grey and the writers for the episode forgot that her telekinetic powers give her limited flight ability as well as the ability to slow falls, both of which she has demonstrated in other episodes.
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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