This is not a blocking problem. Even if you block the first hit, the second one will still be faster than anything you can pull off (only some 1h players are lame enough to do this, but still)
not quite right, to pull this 2nd "abooz" spam of, there are 2 things to be considered:
1. holding the first attack open a longer. That doesn't change the speed of the second one but freezes the nervous system of some opponents
2. don't change movement direction, best done in a left circle from what i have seen sofar. If you change only slightly your movement and may it be only to target a second dude the spam attack is likely not going to work
Then again if you get at someone who is going to do this, aslong you and him strafe evenly and you are not going so much for the sound but more for the animation you will be able to counter this left hand spam. Still it is really annoying and myself is using it like one out of 30-50 attacks. Jacki you bastard, you do it all the time Renegate not that often but still like very 3rd attack and only because of that fighting you guys is a pain in the a**
It is not animation aboose but knowing exactly how the game mechanics work!
EDIT: and what DAhli said