I believe McCarron and KK weren't consensus BPA at the time. Correct me if I am wrong, but that is what I remember.
To get back to Caufield, it's so silly that teams continue to make these sorts of mistakes at the draft table. A shot like that and the offensive instincts to use it can't be taught. Players can work on their athleticism, commitment, fitness, defensive game (though a little harder). But those instincts, those are rare.
The fear of size, especially in today's game is so ridiculous.
McCarron was nuts, KK was a reach but maybe not a crazy reach, unlike McCarron there were arguments for the pick.
The NHL still encourages bullying and does not expect small players to survive. Tom Wilson and Wayne Simmonds were taking advantage of that the last day or two. Historically a significant number of small players who were not insanely fast have not been able to play at higher levels. There were always exceptions and there are more now.
The habs have often taken the wrong player from an effective junior line, we'll get to compare Hughes and Caufield.
Caufield looks awesome but he improved a lot in the last two years, speed, play away from the puck... If he'd been drafted third overall and immediately gone to the NHL I doubt it would have helped his development.