As an advocate of both lethal and non-lethal force, here is my critique on the article.
Having been sprayed multiple times at a police academy and having deployed pepper spray, I can tell you it takes a **** of a man to be immune from the effects of pepper spray. Infact I have never seen anyone immune from it, I have seen officers overcome the effects of it to a certain extent, but they were highly motivated because the training was centered around overcoming the effects in the event that your adversary used it on you, their ability to perform is highly diminished. The training is designed to illustrate to you how you might function having been sprayed. You might expect that, one might be able to punch a bag for 30 seconds to impress his boss. But these are not the kind of people you would deploy against, the people that you need to protect yourself from are pukes and punks. You are in an altercation with vermin not a tactical ops or swat team member.
None of his points are valid reason not to deploy pepper spray, but perhaps some are reasons to deploy a different defense. There is such thing as the escalation of force model. At the bottom non lethal, at the top lethal. At my home at 3:am there will be no pepper spray deployment, it will be a 12 ga pump shotgun loaded with 00 buck. the first round being a 1.25 ounce slug. I do not think that an advocate of pepper spray is suggesting you use it to fend off a rapist or an intruder. What they are suggesting is that you use non-lethal in non-lethal situations. I'm guessing 99% of any need for a weapon would fall to a non-lethal and 1% would fall to a lethal. All this is predicated on the off-chance that you need a weapon in the first place.
He mentions "tap rack bang," well its "tap rack and reassess" and if you can do that then you can deploy a non-lethal and transition to lethal. Transitioning is important, you should be able to transition from a non lethal (asp, pepper spray, baton, BB bat) to handgun, to shot gun and back to any selection you have available.
The real reason one must not rely on pepper spray, and it was not addressed in the pro gun anti pepper spray article, is that pepper spray is problematic when addressing multiple adversaries. But then I have already mentioned that perhaps another weapon should be deployed during that 1% chance when you fear for your life or grievous bodily harm.
Notice at the bottom of the article he advocates his gun selection and his knife selection. I gotta tell you, unless you are a trained knife fighter, I would not waste my time carrying such a knife. I would carry an extra magazine instead.