OK, we shouldn't get too hung up on this; "unacceptable" is obviously hyperbolic! I won't bother with a point-by-point rebuttal, just summarise by saying that t

OK, we shouldn't get too hung up on this; "unacceptable" is obviously hyperbolic! I won't bother with a point-by-point rebuttal, just summarise by saying that this is clearly a blog post, and PDF is completely wrong for a blog post. For the author to get something relating to usability so fundamentally wrong in a post about usability just entirely undermines their argument.