Block strike is the drill most fighters use to work on this.
The idea of block strike is to give you the muscle memory and ability to read predictable responses to common shots.
Set up with a partner a sword lengths apart (use similar length weapons) You swing for a target area, they block, they swing for a target area, you block, repeat for one minute. Swap hands and do it with your left, do it for one minute.
The drill should last 4 minutes with 4 1 minute sections with people using different hands.
Person A Right, Person B right
Person A left, Person B right
Person A left, Person B left
Person A right, Person B left
I know the drill, I use it occasionally, I don't preach it as much as some so I don't have the best discription of it. It will help you though with reaction time.
Other tips for increaseing reaction time. Make some REALLY lightweight weapons, im talking 4-5 ounces and spar with them. The idea is that with faster weapons you have to react faster. Don't do this for all of practice, and don't only use them as they allow bad form for quickness (all arming of shots) its only to increase hand and read speed.
Arguing with a herald is like wrestling with a pig. First you get really dirty and muddy, and then, after a while, you begin to realize the pig is enjoying himself.
King Varadin McButterpants
Elite Blood Falcon