Having been issued with "pepper spray" for personal defense, and having trained with the stuff, I can tell you that there are a few factors that limit its usefulness. Chief of these is air current movement and the risk of cross contamination. Believe me when I tell you, that if this stuff works on bears and dogs, it will also work on humans -- and the user is a human. A little breeze can carry the capsicum spray back in your face, and render you useless to defend yourself.
Under ideal conditions (if they ever exist) it can be effective, but we were always told to be aware of cross contamination, and even a little goes a long way in the wrong direction.
But and it is a big but, I am no expert on bear attacks or the usefulness of spray on bears. I do know 00Buck is very effective -- been there and done that quite a few times.
