Other mistake: When the Alexandria Group are at the Hilltop trying to convince Gregory to join them in their fight against the Saviors, we can see the actresses who play Michonne and Maggie trying to hold in their laughter. (00:06:02)
Continuity mistake: When they get back to the community after stealing all explosives from the road, the Saviors show up and search for Daryl. When they do, that's when they show a one-second clip of the guy Dwight killed a few episodes back, the guy who said there was nothing to go back to. The guy is then shown to be a walker in the defense yard of the Saviors. So, how is he shutting the van doors of a vehicle in this episode? (00:43:12)
Revealing mistake: When the two cars drive down the freeway with the cable in-between them, there is no blood or body parts on the cars at the end despite the carnage, suggesting CGI effects.
Answer: The walkers could have knocked them down more than once. There may have been another wave that knocked down the fence earlier and they're going to put it up again soon.
Captain Defenestrator