I would think that the Combat Knife would have more application for defense against melee combat than offense. Ideally, in a situation of a soldier with a knife attempting a melee strike against another soldier with a knife, there would be a chance of missing, and a chance for reduced damage against the knife wielder. Of course, the Kerrblade thoroughly trumps the Combat Knife, and so miss/reduce chance would be almost zero, but once the Monomolecular Knife becomes available, the playing field evens a bit. Now, in the case of a block or damage reduction, there could be a chance that the defending blade is destroyed by the blow it is protecting against. There may also be some lesser consideration for this with soldier weapons; lighter weapons have a higher chance of reducing/blocking, but heavier weapons are more likely to absorb the entire hit and less likely to be destroyed. A Kerrblade in both hands, mind you, may make the soldier almost unattckable in melee, but that does mean sacrificing any ranged potential.