I like the idea. Besides, most soldiers carry a knife of some sort.
Honestly it's a much needed tool to cover the weaknesses of all the classes, Melee Combat. Soldiers get swarmed easily, with the blade for quick kills they can force their enemies to back off at range where a Soldier class is more confortable will killing. For Vanguards, it's a needed tool so that when they do close the distance and get into melee range they have an ablity that can actually kill at that range. For Infiltrators, the new stealth kills allow them to actually sneak up and slit someone's throat which allows them to embed themselves deeper into a position where they can level the battlefield without being touched. Engineers should be hot on the heels of their Vanguard counterparts as their job is to blow then enemy's frontlines wide open. Once they force an enemy out of cover they can kill them. That simple. As for the Adept and the Sentenal, now they have the ability to do some actual damage instead of hang back and DOT everyone. This is good because BioWare has promised an increase in combat difficulty and speed. If you aren't used to playing ME2 on Veteran or Hardcore difficulty, save your money and don't get ME3. I hope to see the rest of you in Reaper created hell! :) *leaps in feet first*