Revealing mistake: At the end of the episode when Tuco shows up at Walter's house in the backseat of Jesse's car, he tells Walter to get in. As they drive off, the shot pans out to show the street sign across from Walter's house. The sign says Piermont, which is the real name of the street. In the show, the Whites live on Negra Arroyo Lane. (00:48:00)
Plot hole: Preparing to steal methylamine from the train, Walt, Jesse and Mike measure off a predetermined distance from the railroad crossing, which happens to coincide with a handy arroyo, where they bury their tanks. Problem is that they couldn't have known that distance (calculated by knowing the position of the methylamine tanker car in the train) until Lydia told them. But she didn't call that info in until the night after they'd already buried the tanks.
Character mistake: When Hank is brought to the hospital with gunshot wounds, the ambulance and its two EMTs are met outside by two doctors. One doctor says "Let's get him two grams of oxygen. What's his hemoglobin?" This episode's technical adviser was perhaps away for this scene. How much exactly is two grams of oxygen? Orders for administering oxygen would be given in liters, such as two liters per minute (LPM). The line is presumably meant to be 'two liters of oxygen'. (00:02:25)
Factual error: When going over the logistics of the plan to kill the ten men in prison, Jack tells Walt that killing Osama Bin Laden was less complicated. Breaking Bad takes place over a period of two years, beginning with Walt's birthday in 2008, and ending on his birthday in 2010. Bin Laden wasn't killed until May of 2011. (00:15:23)
Factual error: The final scene of the episode, the cousins are hiding with other migrants amid a farm truck's bales of straw. One of the migrants claims they are in Texas. However, the mountains in the distance are the Manzano Mountains which are just several miles southeast of Albuquerque, more than 200 miles away from the border with Texas and Mexico. The migrant claims he has gone through this route 3 times, so it is unlikely this would simply be a character mistake.
Factual error: In the opening scene for the episode, a character commits suicide by electrocuting themselves with a defibrillator. The device used was an AED (automated external defibrillator) which analyses the electrical rhythm of the heart and only delivers a shock when the heart rhythm is ventricular tachycardia or ventricular fibrillation. In this case, the device would not have delivered a shock as the person did not have both ECG electrodes attached and therefore would not have detected a cardiac rhythm. The person would also have had a normal heart rhythm.
Other mistake: Throughout the show, during the into credits, people's names have 1 or 2 letters replaced by green characters to symbolise elements from the periodic table. However, Michael Slovis has the 'Ch' highlighted. There is no 'Ch' on the periodic table. (00:03:20)
Factual error: As demonstrated in the earlier scene where Leonel shot the truck driver/arms dealer, bulletproof vests do not make the wearer immune to bullets. Bulletproof vests are only designed to stop penetrating injury- they do not counteract the high energy of an impacting round, which can easily break ribs and cause internal injury. When Hank empties Leonel's dropped gun into Marco, Marco is barely staggered despite the fact that he just took five rapidly fired bullets in quick succession to his upper chest. That many hits at such close range in such a small zone would have, at minimum, shattered several of Marco's ribs and potentially punctured one or both of his lungs - both critical and incapacitating injuries on their own. As a result, Marco should have been unable to lift his gun to shoot Hank twice in the chest, much less swing an axe. Additionally, at least one bullet appears to strike Marco's clavicle and upper shoulder- both areas that are not protected by the vest. (00:44:00 - 00:45:00)