Here's his article in the NYTimes. The man's tone is so breezily arrogant:
Yoo's writing style is primarily academic, yet oddly dependent on slippery non-academic language, with the additional quirk of "popular audience jokey-ness" that falls dead flat. If he can read and interpret Kagan's writing, he evidently does not know how to write about it effectively in a popular outlet like the NYTimes. Note the strained sentence structure, with commas firing out staccato-style:
But for Ms. Kagan, finding this authority in the Constitution was a bridge too far, a view that put her firmly in the camp of those who see the president’s powers as circumscribed.
She assiduously rejected any claim that presidents may manage the many functions of the vast administrative state because of their constitutional position as chief executive, a view she attributed to “unitarians.” (These are not your mother’s non-Trinitarian Christians.) Instead, she concluded, the framers did not see the Constitution’s vesting of the nation’s “executive power” solely in the president as a grant of any substantive power.
Regarding the content of the article, if John Yoo is uncomfortable with Kagan's views of the unitary executive theory of the presidency, then my confidence in her just increased a lot.
From the time of George Washington, presidents have understood Article II to grant them the authority to hire and fire all subordinate officers of the United States, and hence command their activities, even though the Constitution mentions only the power to appoint, not to remove.