Stewart and Cohen redeemed themselves somewhat in my eyes, for the whole lies-to-children nonsense, with this quote:
"If you want to reduce carbon dioxide permanently, and not just cut short-term emissions, the best bet is to build up a big library at home, locking carbon into paper..."
proving to me, at least, that they are not completely irredeemable, but honestly I still can't say I like them much. I can't fault their explanation of the science, and I'm enjoying their science writing, but when they start trying to talk about topics unrelated to science (like, again, the lies-to-children nonsense, or later in the book the concept of a soul) they come across at best as arrogant, disrespectful and condescending, and at worst, full of shit. Stewart and Cohen repeatedly stress the point that science is about not knowing the answers, that science is about the questions, and then proceed to speak with false authority about things that are purely subjective by any standard.
Everybody makes their own decisions about matters of faith and deism, but it would be in the best interests of a lot of scientists, including these two*, to remember that a very large number of the most important discoveries/theories in science were the result of work done by priests and monks**. They didn't find their faith to be in conflict with their work, so why the hell should anyone else?
* In fairness, Stewart and Cohen don't actually cross the line into denigrating those who believe in something greater than man, but they do dance across the line once or twice, particularly in terms of the soul. It's their prerogative to believe or disbelieve, but to try to state that they know nothing survives death is where they go wrong; they don't know. Unless, you know, one of them is a zombie, but then they're still wrong.
** The list is so long wikipedia has to list them alphabetically: