Hi Gavin
Glad you included a warning on the danger using this point.
the danger is maxed when lets say it is used on a sitting opponent who refused to move from the floor or a chair while drunk or just protesting..
Security personel will often gouge or strike from behind pushing forward and upwards. If this is done very hard or with a wooden control stick death may occur.
So be careful when tw-17 is used for real. As a former corrections officer in a max state prison I can tell you its easy to increase the level of force without realizing it.
Alan