Bottom line in all this is that Michael W's characterization, generally speaking, is accurate.
We could argue back and forth all day long as to exactly how every QB in the NFL should be characterized, but at the end of the day, Michaels's general idea is correct. Bledsoe has been a quality NFL QB, and that is mainly due to the quality of his throwing arm. The mental side is his drawback, and has kept him from being labled among the NFL elite at the position despite bigtime career numbers in certain categories (yardage and TD's).
Guys like Bradshaw also fall in that category, but his crossover into joining the greats in people's minds is due more to having been on great teams that won Super Bowls than his own personal talent.
At the other end of the spectrum are guys like Montana, who did not have particularly strong physical abilities, but his instincts and intellegence elevated him to one of the top QB's ever.
Elway, in my mind, fits somewhere in between. I think it's fair to say that Elway matured as he got older, developing beyond the player he was in his early years who relied almost solely on athleticism and a big arm to a much more efficient QB who learned the value of making better decsions, minimizing mistakes and focusing on higher percentage passes.