Good point, and as most people are iodine deficient, and iodine is an essential element, I would hate to see people discouraged from supplementing iodine because of a few pimples they may or may not get.
I agree to an extent. Most people should supplement in some form with iodine, but at the same time they need to be careful about going overboard. And the acne sensitivity in people is when the EXCESS iodine is being excreted through the pores.
It is like with another halogen, fluoride. We need small amounts of natural fluoride for strong bones and teeth. If we ingest too much fluoride though we end up with problems such as fluorosis. These are examples of too much of a good thing.