My emergency medical experience isn't all that extensive, but I have been involved in about two hundred wilderness accident scenes where significant bleeding occurred. In all cases, direct pressure on the wound worked just fine. One of these situations was the virtual amputation (the job was completed later in the hospital) of an arm. This stuff may have applications with battlefield situations, but I don't think it is necessary for most "normal" traumas.

I would be very interested in the experience and opinions of some of our really experienced medical folks.