Why do idiots say how "using your helmet as a weapon" isn't how they were taught when

[Jake the Snake]

players say otherwise? there was this douchebag idiot named "Tyler" and some other idiot telling me how "leading with your helmet is not the way they were taught" lol as if I should believe him...there's been nfl players and/or nfl commentators say "that's the way they were taught" and "that's the way football is meant to be played"

http://sports.yahoo.com/nfl/news?slug=ap-helmethits-quotes

these idiots also said it would lead to breaking your own neck or whatever

if that's the case then how come defensive players against it and have said "it's the way football is meant to be played"
haha if it's not intentional then how come so many players have a problem with it?