They should be required to surround a place and give a loudspeaker notification to say they are coming in...and 5 seconds later make the move. No-knock raids cause unnecessary deaths on both sides and make it harder for some to understand the danger to regular officers that get shot when responding to complaints or serving papers.
If they give notification and then have to use overwhelming force, so be it.
Five seconds is way to short of a time to answer the door.
My unpublished research shows and average time of 15 seconds to answer the door.
It stretches out to two minutes when people are in the shower, taking a cake out of the oven, changing a baby, or many other things.
Waiting for someone to answer the door for a warrant should be at least a minute, if not two.