You have a very good grasp of the many pieces in play here. I can't keep it all straight and whenever I hear about something that threatens the investigation I freak out a little.
I do have faith in Mueller. He seems methodical, precise, thorough. And I do believe he is a numbers guy as well. 
My favorite thing about him is that he doesn't seek publicity or leak anything about his strategy. He just quietly gets it done.
My opinion, the freakouts we've witnessed past few days from Fredo are partly due to the fact that he knows his son will be arrested soon. Midterms have an awful lot to do with it but his son would be his main worry. Not that he worries about his son at all. He loves no one, least of all himself. No, he's thinking about how bad he will look when the kid is arrested.
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