Well we know why they waited this long.
He lost the thread multiple times and employed a coping mechanism I have seen repeatedly in family members as they slipped into dementia:
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Some version of a rambling answer then "so do you want me to keep going?" or "Do you want more detail?" because he couldn't complete the thought or find a finish.
When he switched from immigration to discussing the filibuster, it got bad.
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At one point he said this:
“I have never been particularly poor at calculating how to get things done in the United States Senate. So the best way to get something done, if you, if you hold near and dear to you that you like to be able to, anyway. . . ” and just trailed off.
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Spoke best when he was most sharply on a tangent, not answering with policy. I.e. great story (seriously) about his ancestor coming from Ireland.
Also a coping method. When my dad was in early stages of Alzheimer's, he could tell his old stories beautifully; new stuff not.
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Note that reporters did not raise their hands so he could call them by name. Rather he had cards with their names on them, in a set order, and he read the name off the card, then looked to see who stood up.
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Any person watching that sad performance with an objective eye knows what they saw.
On the policy side: So his plan is to allow reporters access to border sites only AFTER he's fixed the problems. Hmm. OK, that's . . .transparent.
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7/6 (sorry)
On policy he also said of China: "China has an overall goal and I don't criticize their goal."