Good article.
Following are just my opinion, as always, and are not medical advice in any way, but observations based on my research.
1. I-131, the primary radioactive isotope of iodine, is present in great quantities in gaseous releases from nuclear powered electrical generating plants. Using a thyroid iodine blocker in such a situation is extremely important.
2. While I-131 is produced by nuclear weapon detonations, there is not all that much of it. What does not condense onto particulate matter is spread out immediately, and dissipates relatively quickly, unlike the steady stream that can continue to pour from a power plant leak. Any that has bonded to particulate matter and comes down as fallout is not easily absorbed by the body unless ingested. Future uptake by some plants is possible. Since taking a thyroid blocker when not needed can have adverse effects on the thyroid, I, personally, do not consider thyroid blockers as part of my nuclear device preps.
3. The halving thicknesses given in the article are somewhat more conservative than those usually accepted, but not the most conservative I have found. Just be aware of the fact that there are some difference of opinions in the sheltering industry as to what will reduce fallout radiation by one half.
Just my opinion.