Yes, we've had many discussions about Rocco's possible involvement in the Tahoe shooting, or of his being the main culprit. But it all pales before the fact that Fredo admitted that he betrayed Michael. And, even though neither he nor Michael mentioned the drapes, the open drapes were the key element in the plan to whack Michael in his bedroom. Fredo also admitted to his motivation for betraying Michael ("He said there'd be something in it for me"), and shouted out his resentment over being passed over, whereas Rocco seemingly had no real motivation to betray his boss.

PB: Great to see you again! Hope you'll stick around!