There's always room for disagreement because economics is the dismal science (as one famous line put it, Harry Truman wanted to find a one-handed economist - so they wouldn't always answer "X could happen, on the other hand, Y could happen), and answers aren't as binary as they sometimes are in the hard sciences. I'm curious to see what Rogoff and Reinhart respond to this with.
Edit: thanks for the Ritholz piece - hadn't seen that. I certainly am not claiming that there's no mistake - I just want to see what the defendants in this have to say, so to speak.