Yup; on two occasions I wrote 50000-word novels in the course of a week, but both times, it was the summer holidays, I had no commitments whatsoever, and I went online for a maximum of ten minutes each day - if at all. (Though how I managed that, I have no idea.) And talking about novels definitely slows them down - apart from taking up time, you get much fonder of talking about them than actually writing them.

I think I could write 50000 words of personal utter bumph in the space of twenty four hours, if I wanted to: I can type at over 2000 words an hour, and I'm good enough at rambling to keep going for that long. But fiction? No. The most I've ever done in a day, fiction-wise, was 10000 words, and that meant not going online until late evening.