I think that the term "kicker" comes from the British word kicking strap which is the same as a boom vang or "vang". The two do the same job. As for using a vang as a preventer, it is very common and sometimes termed a prevang.
The job of the preventer is to prevent accidental boom jibes but expecting it to work in high winds or extreme conditions is looking for trouble. I believe that preventers are best when used when the boat is rolling and the boom may flop from one side to the other (especially in light airs). Expecting it to hold the boom in place in strong winds when the full force of the wind hits the back of the sail is unreasonable. Something is going to give. Hopefully the preventer will be the weak point, not the boom. In those high wind or extreme conditions the boom brake becomes the device of choice because it allows the boom to cross the centreline but dissipates the powerful boom breaking, sail ripping, gooseneck snapping forces. When sailing off the wind in extreme conditions, particular care should be taken to avoid jibing and in those conditions I would not use a prevang. In lighter airs where the boom will not stay in place because of rolling a prevang is perfect.
There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries.
Shakespeare, Julius Caesar IV, iii, 217