There's another variable to consider.
The amount of time it takes to write a novel is not only commensurate with a person's talent and skill, but also in the amount of time they spend writing each day. Someone with only one hour available every day will take longer to write a novel than someone who writes for six hours a day.
Given a reasonable amount of time to write each day, I don't see writing two novels a year as anything extraordinary. Anything more than that starts getting impressive though.
I think many, many writers out there write a lot faster than most realize. They use pseudonyms, they write novels fast, but rather than releasing more than a book or two per year, they write reams and reams of short stories, articles, screenplays, and you name it.
I'm much like this. I've written and sold a novel in three weeks, and another, of only fifty thousand words, in ten days. But novels are not my priority. I write 2,500 final draft words per day with no strain. This is five hours writing time.
The majority of these words go to other things, such as short stories, articles, screenplays, essays, or you name it. These things are my bread and butter, and I love the diversity.
Anyway, you can't really look at how many novels a writer releases each year and judge his writing speed from this alone. Between pseudonyms, ghosted books for certain publisher's book lines, short stories, articles, screenplays, and you name it, many writers are extremely prolific, but it doesn't show in how many books come out per year.
I know so many prolific writers, and I've read about so many more, that I really don't get impressed until the writer hits a book per month. Or, more accurately, hits anywhere from seventy-five to one hundred thousand words per month, whatever those words go to.
At five hours per day, five days per week, I write fifty thousand words per month on a regular basis, but when deadlines or multiple projects force me to add hours and days, I can double this without killing myself. I won't have any much free time because to hit one hundred thousand words I have to write seven hours per day, seven days per week, and I
hate putting in that much time, though some writers, such as Dean Koontz, put in considerably more.
I can, if need be, keep such a schedule for three or four months before I burn out and need some time off, but I didn't become a writer because I wanted to work long hours seven days per week, so I limit how often I let this happen. Unfortunately, it's happening right now.
I would say I'd writer faster were I a better typist, but I'm not sure it's true. Nancy Kress is pretty darned prolific, really, really good, and she types with one finger on her right hand.
So no matter how fast and well I could
type, I think my writing speed, my brain speed, for final draft words, at least, is five hundred words per hour.