It seems like he was coached. Not sure if you like podcasts but the season of Fiasco about the Iran Contra has an episode all about Oliver North's hearing, and how somebody clearly put a lot of effort into shaping America's perception with little subliminal strategies (like camera angles, delivery of snappy "lines" in response to questions asked by Congress) when he took the stand.

Public persuasion and narrative control by the right is something that they've been pretty skilled at since the Heritage Foundation first came to power under Reagan. The creator of Heritage was actually a broadcast journalist and press secretary before he started the think tank. He was constantly trying to use his connections to the media to manipulate the public and smear his opponents. I think that's one of the most interesting aspects of neocon history and strategy that nobody has ever really paid much attention to at a cost to our country.

Anyway, it looks like they may have tried to do the same with Kash Patel but failed:

Not sure about when he took the notes, but this article says he took them during the hearing