Yes, I forgot.
Again, there's nothing to indicate in the slightest that Fredo was the family's underboss and we Board members have certainly concluded that Fredo was as capable as being an underboss as he was of giving birth.
This wasn't explictely the reason for making this thread though as I'm not really disagreeing with you on this. With not really I mean that I do think the ranks are pretty accurate, although Fredo's role as 'underboss' could have been no more than of symbolic value for the same reasons you mentioned.
I think Michael gave Fredo purposedly the position of underboss to make him feel more important, but everybody knew he had no real power.
Was Frankie the source of the FBI's info? Well, possibly. But, as you point out (and about which I have opined endlessly on this Board) how does the most power ful Mafia family in the country with 1,000 soldiers get along with just a couple of capos?
As you're refering to Clemenza's statement in the novel, I imagine this was meant to be the Corleone's entire criminal network, including associates.
If the chart omly illustrates the Nevada faction, why is Frankie part of it? Yes, it is a movie.
You're right about this. I thought about this myself and I think (just my imagination) that Frank obviously had to include himself on the chart. But I think he only "ratted" on the men who were personally led by Michael in Nevada.
For me that's the only decent explanation (besides it's ofcourse just a movie).