The Accuracy and Careful gifts allow one to place his strikes at less heavily armoured parts of the opponent's body/more heavily armoured parts of the body, or even stab people in the groin through plate armour. Which does actually make sense, groin-stabbing was an authentic method of dealing with plate-clad opponents. (What, you think knights were knightly?)
The progressive schools of swordsmanship allow students to roll against a target number of 7 for Duck and Weave, a maneuver that normally requires a target number of 9. This maneuver allows the defender to reduce an attacker's CP for every margin of success the defender wins by.
Magic. Broken on purpose. A level 3 movement spell (target number 8) is capable of instantly accelerating up to 2,000 pounds of material to lightspeed. Suffice to say, there is no defense.
Dedicated grapplers in heavy armor are even more dangerous here than in Exalted. The advantage for massively outweighing your grabbed opponent is nearly impossible for anyone not VERY well built for grappling to overcome.