It seems that there are so many ways to get through a guard in this game that I seldom block. If you can mix it up enough and know good combos, you're golden. The only people that are trouble then are the ones that know how to Hold well. I usually go straight to a S or A or B lobby when I play, and, even at a F rating, I can still perplex high level players with an assortment of attacks. Once you become pretty unpredictable, even Holds are out and those high level players only end up beating you because they understand how to execute powerful combinations. I watched a B defeat an S last night with mid and low punches with a stun thrown in here and there and the S player didn't know what to do. That's all he did. I beat 3 S rated players since I started playing using the same kind of tactics. Those stuns and critical stuns are crazy.