As far as my favorite poltical biographies go, I think the ones that gave me the most understanding of politics was the Robert A Caro biographies, "The Power Broker" and "The Years of Lyndon Johnson".
I don't know, but I wrote nearly 3000 words on the last book review I did. I'd say I spend less time than 90 minutes per chapter. I'm also sharing the reviews, which I find the most rewarding part.
I recently started writing reviews of each book I read. I found it helps me retain the contents of the book and often people give positive feedback about what they learned from my review.
I'm not a biologist, but I know from other biologist that is often difficult to cultivate cells in a lab. Kudos to him for mastering such a difficult art