do bloodwells on stabbing implements really work??

all of my purpose-built stabbing implements have blood wells fitted. do these really speed the progress of the blade through flesh or are they akin to the ground effects devices now standard on german family sedans; i.e faster only in your mind. the question arose at a recent suicide i attended. conducted in the traditional japanese manner (and you think the sunday mass drags!!), i happened to notice that none of the various katanas, etc. had blood wells. and yet, as events would later prove (as if james clavell hadn't already), the blades were admirably suited to their purpose. are western swordsman weaker/lazier/in a bigger hurry than their eastern counterparts?? are western victims juicier?? is there some issue with fatty tissue?? i'm on the air in about six minutes so any info would be much appreciated. now that i'm world-wide i like to inject a modicum of verity into the b-casts-- if only to amuse myself.