sk89q/worldedit — comment on commit 76f1ea9cf219a3d0924ee4567ea509dbb171dead
File:  line 0
By Jadedwolf:

The point was there should be a way to select an area and turn off psychics while you build there.
That way you can do lots of things beyond just portal stacking. Including water/lava flow torches needing to be attached to something, sand falling, etc, etc.