yup, WWP = portable table edge for anything not in a tank.
In table quarters it opens up the 3/4 of the table.
In Dawn of war it cuts the distances in half for walking units.
In Pitched battle it can overload a flank, or act as an anchor, or spearhead.
It is also impassable and blocks LOS- giving cover...making other units go around it, etc. Tactical uses are very varied and having one in a list is nothing to sneeze at.