There is a danger in this tabula rasa sort of thinking. If we think only of imaginary scenarios and "in theory this is how it works", we're likely to ignore the very real consequences of this awful practice. Ms Taylor isn't the first person to die in this situation (innocent person killed entirely due to police incompetence); neither is she the thousandth. Lots of police die from no-knocks gone awry as well. There is no reason for any of this. If police know where the suspect is located, they may collect her or him at any time. When the suspect is a regular person with a regular job, why not make an arrest when she or he leaves the house to go to work in the morning? How about arresting the suspect at work, with no opportunity to hide evidence or resist?
The "nightmare scenario" that cynical police spin for credulous judges is that drugs might be flushed down a toilet. But drug prohibition is itself cynical and evil. Prohibition has only ever harmed American society. As we collectively wake from our long nightmare of drug enforcement, we must do away with all the insidious menaces that it has inspired. Our police will not be replaced overnight with "responsible" authoritarians, so we must not "imagine" we can safely allow them the tools of authoritarian tyranny, on the off chance that they might not be used in the way they have always been used. You write as if it's only because of "unprofessional" actions that Ms Taylor was killed. In fact, "unprofessionalism" is why we are blaming the police, but people like Ms Taylor are killed in no-knock raids even when every action is performed in adequately "professional" fashion. Occasionally no one dies senselessly, but these raids are always dangerous and unnecessary. That is a practical truth, which overrides "objective" theory.
I hope folks read your comment and follow the link, it's worth the read.
Either the amount shouldn't matter or you shouldn't be able to flush it all at once (also, as if "plumbing forensics" didn't exist)