Agree with all your points TB plus, as I have posted before, Fredo lied to Mike in the boathouse scene. He sais he didn't know it would be a hit. He knew.
How do you figure that? Remember when Johnny ola called him and Fredo specifically said, "You guys lied to me"
I think the lie was that there was something in it or Fredo. They never gave him anything.
I dont buy that at all it doesnt fit with Fredo's character. Fredo is a womanizer and an idiot but he probably the only corleone brother who has a soul lol and he cares about his family. Mike by part 2 had become a psychopath with no empathy for anybody