"He'd kill us if he had the chance" - I STILL hate this
I've always, always hated the way they replay this line and change the inflection (and thus the meaning). In hindsight I get now that it wasn't meant to be literal and rather the movie was trying an elegant way to explain what the scheme was.
But still! I don't think that's very intuitive - my initial impression absolutely was that Harry had implausibly "misheard" or misremembered the conversation (rather than simply misunderstood or been tricked) and that the movie had cheated in order to present that. And honestly that still strikes me as the more natural way to read that sequence, and it ends up derailing the ending pretty severely. In fact it comes dangerously close to ruining the whole movie for me!