I have no experience with Kydex, but I have had to use a pair of linesman's pliers and/or Vise-Grips to hold a saw blade once or 100 times.
A great, pretty cheap tool to have around is a jab saw handle, like this:
http://www.stanleytools.com/default....&SDesc=Jab+Saw
You can put just about any blade in it, jigsaw, hacksaw, sawzall, etc., and makes life a lot easier, and save the Vise-Grips for what they do best, completely rounding off bolt heads.