The "no-knock" tactic should be called ambushing and when you ambush people they get startled and are prone to act out of the normal human behavior of self preservation.
On the scale of stupidity the no-knock ambush is probably a 9.
Lets not forget the official fairytale that people in this country are presumed innocent until proven guilty. Ambushing a pot-smoker at 5:30 in the morning damaging his house and risking the lives of everyone involved is not presuming innocence, its presuming guilt. This guy did not have the codes to a nuclear bomb...he was an alleged common drug dealer.