I've parsed out a couple items and it seems that recuperation time is the time it takes you to recuperate between swings. For example a heavy sword or hammer will take longer between swings than a light dagger or shortsword. The "Speed" modifier on a weapon somehow speads it up. I'm not sure if that is a direct subtraction from your recuperation time or some other formula. All my parsing efforts have been visual with a second hand timer, I've yet to come across a program that runs behind DD and records your dmg done like I used in Everquest. My best guess is that a weapon with a recuperation time of 15 and a speed modifier of 5 would have an actual recuperation time of 10 before taking into account any skill specializations. Not 100% sure though.
Calonderiel