That's all possible.
It's interesting that last night a main discussion point was that Dr. Brewer did a wonderful job laying the groundwork for Dr. Diamond's testimony. He wasn't great as a standalone witness, but he was amazing in clearing the way for Dr. Diamond. Additionally, there were numerous comments from various posters how it would be disastrous if Dr. Diamond didn't testify.
Now that it is a fact that Dr. Diamond isn't showing there are a number of plausible and reasonable explanations. I am just surprised that I did not see the same explanations last night. If Dr. Diamond was not needed, where were those opinions last night?
My opinion only - Dr. Diamond's appearance is disastrous to the defense team.
Oh, I was sure last night that my Machiavellian pawn -Queen scheme must be so. But what I also said, after laboring over his testimony, word by word, was thst imo he had done a perfectly fine job, and in fact, had bested Boring more than once.
I hoped for and anticipated Diamond. Things change. I actually felt a sense of dread when I saw he wasn't appearing for the DT. After taking a deep breath and going back over Brewer's testimony and guessing why he isn't testifying , I'm concluding there whatever the reason, I believe the DT, Ross, and Diamond weighed the options and did what they thought was in RH's best interests, here this close to the end
Trial strategy is fluid, I think Kilgore is likely exceptionally good at reading juries, and Diamond would never have taken any steps towards testifying if he thought Ross killed Cooper deliberately.
I trust they made the right choice...and would love to hear the whys, if we ever will.
(And PS Peach-- isn't that an evolving opinion of yours I see?

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