[weby]

I think it is to distinguish Psionic teleportation from the magic kind. Basically psionics is supposed to give the science feel and having to specify distances+vectors or coordinates instead of "home" or similar feeling based thing is supposed to be part of that.

Only the blink is without blind and that seems to be supposed to model a reflex uncontrolled use of the ability where the subconcious does that figuring of coordinates for you to find any safe spot..

Edit: So for the teleport sword question: you would need to be able to fix the coordinates clearly enough for that teleporting to be possible and that seems perfectly fine if the actual though is "teleporation is the ability to move things from known coorninates X1,Y1,Z1 to known coordinates X2,Y2,Z2 and not a spell of "Moving object X to location named Y or seen by you".