In other words, the lubricant decreases the coefficient of friction on all faces of the knife and will increase the knife life by significant percentages, but most importantly, the self sharpening effect will be enhanced because {HEAD ~ the friction} on the upper surface will be reduced to {TAIL ~ a significantly greater extent} 
reduced to
In other words , the lubricant decreases the coefficient of friction on all faces of the knife and will increase the knife life by significant percentages , but most importantly , the self sharpening effect will be enhanced because { HEAD ~ the friction } on the upper surface will be reduced to { TAIL ~ a significantly greater extent }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL