i am the author and i didn't mean to be wishy-washy about it. i read several of the papers involved and think it's more likely than not that qwerty was designed for fast typing, or at least not designed to type slowly. but i wouldn't say it's a done deal -- the paper i cited gives the most convincing argument, imo, but it didn't move me up to 100% confidence or anything. i didn't want to give the appearance of being too certain, because i'm not.