(CNN) Ty Cobb -- no, not that Ty Cobb -- isn't a household name outside of Washington legal circles.

But Cobb, who spent almost a year from July 2017 to May 2018 as the White House lawyer leading the response to special counsel Robert Mueller's probe, may have, in retrospect, made one of the most consequential decisions in the presidency of Donald Trump: To cooperate fully with Mueller's investigation.

Cobb's thinking, according to reporting over the past two years, was that by fully cooperating with Mueller's investigation, Trump and his broader White House would ensure that the probe was short-lived.

"I'd be embarrassed if this is still haunting the White House by Thanksgiving and worse if it's still haunting him by year end," Cobb told Reuters in August 2017(!) , adding: "I think the relevant areas of inquiry by the special counsel are narrow."

To that end, Cobb urged Trump not to publicly attack Mueller -- the former director of the FBI -- or the special counsel probe more broadly. And most importantly, Cobb advised Trump to allow administration officials to broadly cooperate with asks from the special counsel.

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