You can also use an enemy ship to shield yourself from his friends. The AI has no qualms about friendly fire. That being said, it'd be nice if the throttle wasn't limited to 4 settings and there was an option to match speeds with your target.
Just click the throttle with your mouse to set an arbitrary speed.
I used to bother setting speeds in increments of 1/8th, but I don't anymore because I've found it really dosen't matter. Going a bit slower than the enemy ship is handy in case they make their trademark unexpected stops.