well, I nuked it. Here's the old post if we need to put it back up at any point:
=== Swing Timer ===
An important piece of information that should be noted is that successfully parrying an attack will reduce the delay before your next attack. The reduction amount is a flat 40% of your normal swing time. The delay cannot be reduced to less than 20% of your weapon?s base swing delay.
For example, let?s say you are using a 3.4 speed two-hand weapon. You attack at time 0. You parry an enemy attack at time 0.5. Your parry reduction value is 40% of 3.4 which is 1.36 seconds. Instead of attacking at time 3.4 you will now attack at time 3.4 ? 1.36 which is 2.04 seconds. If you parry with 0.68 seconds or less remaining in the delay to your next attack then no reduction would take place. If 2.04 to 0.68 seconds remain in your delay for this example then the delay gets reduced to exactly 0.68 seconds, since that is the minimum for this weapon.
Note - the above formula may not be correct. Recent testing has shown that the parry delay may be prorated depending on how far through the swing you are when you parry a mob's attack. This would account for combat log parsing making it look like you cannot affect a swing time to be less than 20% of it's initial value.