Tells and telegraphing are bad.

Shortly after he describes True Guard, Swetnam goes on about hawks for a bit. This is a long winded and rather pretty digression but it eventually comes to a point. The hawk may be fast, but you get precious seconds to prepare when you see their muscles bunch just before they launch into the air.

Recognising tells and reading your opponent is very important- so is eliminating your own tells. Anything you can do to reduce the window where your opponent can legitimately defend himself is a good thing. Preventing telegraphing is also useful in tricking your opponent into believing that a feint is real.

Blade contact allows you to read intent by feel, this works both ways and your opponent can do the same. If your blades are touching- assume that you're shouting out exactly what you're going to do. You may think this is all bollocks, but contact mind reading has been used as entertainment for at least a century and Derren Brown can find an object hidden in Venice using this skill. You will be able to tell that your opponent is about to disengage, become more sensitive and you'll know a lot more.

However, the majority of the reaction time is controlled by keeping distance and framing a good guard- making sure they have to move more to hit you that you need to move to defend yourself and keeping lines closed.

Everyone regardless of school, weapon or suchlike seems to agree that timing and distance are essential. There's a lot of words spouted about what "good time" is, but distance appears to be universal- The longest reach of the two people, plus one inch. (of course, then you've got to close under guard and stuff when you're short or strike as they recover). Recognising tells helps you maintain this distance, your opponent's posture changes when he thinks you're in their range and you can react accordingly.