The Clean Room Infiltration - S8-E11
Stupidity: On the way home from the university after wiping their names from the sign in sheet, Leonard, Howard, and Raj are all singing Jingle Bells. Leonard is driving and has his eyes closed all the way through singing the song, this makes no sense at all giving he should be looking where he's driving.
The One With All The Rugby - S4-E15
Stupidity: Emily tries to help Ross inflict pain on the other rugby players and tells him about one player who doesn't wear a cup. No one who knows rugby would ever wear a cup, it is more hazardous than helpful to wear a cup in rugby as it involves a lot a grinding, and a simple slip or movement could cause serious damages to the male genitals. Especially if these guys are British and well versed in rugby which they are.
Halloween 2: The Ghost of Hetty's Past - S2-E5
Stupidity: If Sam was so worried about conserving oxygen, she should have blown out the candles in The Vault.
Stupidity: When Franklin and Tara are hooking up at the motel, it appears that sunlight is shining through the windows. Franklin is unaffected.
Stupidity: Donna runs in to save everyone from the collapsing pylon, dying in the process, despite the fact that Superboy or Raven, both more powerful/resilient, could have stopped it falling without any issues whatsoever. Not even like anyone was distracted - the fight was over, they were all just standing around.
What If... The Watcher Broke His Oath? - S1-E9
Stupidity: Ultron says he can destroy galaxies with a thought. So regardless of Dr. Strange's protection spells, he could destroy the planet they're all standing on, or evaporate the atmosphere, leaving them all suffocating in space, and just step away from the fight entirely while they die.
I'd Rather Twitch Than Fight - S3-E10
Stupidity: Like most dilemmas on the show, the controversy could have been resolved by witchcraft without Darrin knowing. Why didn't Samantha just twitch a duplicate tweed coat?
Stupidity: With one humongous stretch of luck (Magnum loses the guy he is looking for but TC who just happens to be generally 'in the air' is close for him enough to just be able to do air recon for him, and spot the guy who is still running because he must have gotten take-away food from half a city away on foot), Magnum arrives so close to him that they are in the same street maybe 10 meters apart. Yet Magnum needs another tip from TC and his passengers to spot him getting inside a house, something he could have never missed. (00:16:00)
Iron Man to the Second Power: Part 2 - S1-E10
Stupidity: When the other heroes are watching Iron Man battle his robot duplicate, Julia cheers him on and calls him Tony. This fight is taking place in full view of the public, and the public doesn't know that Tony Stark is Iron Man. They believe that Iron Man is Tony Stark's bodyguard. Julia could have easily revealed Iron Man's secret identity in this moment. (00:17:50)
Camp Redwood - S9-E1
Stupidity: Brooke leaves her apartment window open as she sleeps, even after telling her friends that serial killers (like The Night Stalker) strike during the summer when everybody leaves their windows open.
Stupidity: Eve, the assassin trying to kill the Senator, tells Cole to move or she'll shoot through him, rather than just shooting him. She already killed an agent by shooting him in the back and had plenty of time to just shoot Cole, so there's no reason for her to avoid killing him.
Stupidity: Yoshi, Mario's sidekick who constantly follows him on dangerous adventures and has gone on dangerous adventures by himself, gets scared shitless when confronted by Riptor. This is not how Yoshi would act in a situation like this.
When in Rome - S1-E3
Stupidity: A supposedly covert camera is placed in plain sight on a wall in a crowded room, with a prominent antenna showing, and a blinking blue light. (00:16:55)
Stupidity: In any normal match, 4 players who deliberately charge the keeper and hit him when he already has possession would be sent off or booked, here of course it does not happen. What's more puzzling though, is that the team had as deliberate strategy to injure the keeper, they are shown with evil eyes and grins like homicidal maniacs...but then at the end of the match they exchange pleasantries, handshakes and sincere goodwill wishes.
A Rough Whimper of Insanity - S1-E7
Stupidity: The hacker's VR goggles are not plugged in to anything (despite having a wire for this purpose) when he and Tom sit down at the computer in the teacher's house.
Stupidity: The last remaining Xindi, in desperation, attempts to release the virus over the fan, despite the virus not being fully ready. However, it seems the only reason he didn't release the virus at that time was he had to seek cover from Archer and T'Pol shooting at him and to start shooting back at them. However, he had plenty of cover from the rooftop stairwell, which was right next to the fan, and he had enough time to dump out the contents over the fan.
Stupidity: Mouch is investigating an arson allegation. He states to a lady he's going to do his thing and speak to some of the residents. As he goes down the hall to speak with the residents he passes a huge stain on the carpet that looks like blood or something and walks right past it without stopping. (00:23:57)