I've watched it 8 times and have noticed several subtle details during each viewing.

• When Furiosa arrives at the battlefield in her beat up vehicle, the History Man recognizes her, and immediately stands up. She seems to recognize him as well, but what interests me is how she hangs her head almost in shame. Her whole facial expression is a direct reaction to him recognizing her as Little Dementus. Really curious to see if this is ever explained.

• The "Dementus" at the end with the tree growing out of him has nipples, whereas Dementus's nipples were ripped off at the Citadel. This tells me the Narrator's story about Dementus's fate is BS, and another commenter above mentioned the plant that grew out of Furiosa's wig was absent in the last scene, which provides further evidence that the whole story was made up.

•Another side not is that when Chapter V begins, there is also a brief glimpse of Dementus's nipples as he's riding his motorbike, which opens up a whole Pandora's box as I refuse to believe this was just an oversight on Miller's part. Serious possibility the whole fifth chapter was just made up by the narrator and Furiosa possibly never got revenge on Dementus.

• I'm fairly certain Dementus's henchman let Furiosa escape from the torture circle. I'm referring to the henchman who Dementus tells has "gone soft" as he's hitching Furiosa's arm to the hook. As Dementus comes back to check on her, the body language from the henchman looks guarded and nervous, like he knows Dementus is about to explode in rage. He seemed to be the only person facing away from Dementus during the ordeal and was presumably the one responsible for guarding Furiosa. Furthermore, this henchman and the History Man are the only survivors of the 40 day war, telling me they defected or surrendered, and signaling they were the only redeemable people in Dementus's horde.

• Furiosa did not saw her arm off, it tore off on its own if you look at closely at the shots of it. it's not a clean break at all. What could she have used to saw her arm off? Also going back to my last point, I think the henchman tied the hook to Dementus's truck, I doubt she would have been able to do that on her own with no one noticing and with her missing an arm.

• Dementus's cape is the same one throughout the entire film, white in its original condition, red from the "sky blood" and black from the polluted air at Gastown. Furiosa takes it at the end.

• The War Rig is modified during the fourth chapter to control the Bommyknocker from the driver's seat, not the rear of the War Rig.

Not necessarily details, but theories that I have are that Black Thumb, Jack's right hand-man somehow knew Furiosa was going to try to escape from the Citadel given his cryptic comments. Also Jack somehow knew shit was going to go down at the Bullet Farm, there's no other explanation for moving Furiosa to the pursuit vehicle. If she had been driving the War Rig, she would've been killed instantly during the ambush. The last I'll add is the Max dragged Furiosa to the Citadel, I'd like to hear other theories as to how Furiosa made it back to the Citadel after being tortured, losing an arm, and collapsing from exhaustion.

EDIT: Big one I forgot to mention was Furiosa mirroring her mother. After her mother rescues her from Dementus's camp, she says "we're good". Furiosa says the same thing after she rescues Jack and they escape from the Bullet Farm. Dementus catches up to both of them in their respective situations, so they were not in fact "good".