If a flurry is six strikes in the time a normal dude would hit once...well then they are pretty awesomely fast strikes. You don't seriously suggest that your character should, after each & every strike, check your foe's vital signs and then evaluate whether or not to attack again?

Nonono. You focus, and then unleash them in a blink of an eye. You victim will remain upright for the duration, before dropping down, perplexed and quite dead, regardsless.

"There is no such thing as overkill"
-unknown halfing rogue on steroids.