Thanks for the reminder about titrating down as well.
So, if we believe Iodine is the solution to the problem then whatever toxic poison it displaces which cause the detox symptoms such as bromine makes bromine the problem.
In a fire when water is thrown on steam is given off. Steam rises and oh can it cause problems with this or that. But the source of the problem remains the fire. Please excuse my analogy hope the idea comes across.
My guess is small doses of Iodine cause greater problems such as Bromine clogging excretory organs like the skin, the zits. Or kidneys, kidney pain, than gram doses is large doses saturate the body organs faster thus there is no place for Bromine to hide and cause symptoms. We just pass it out in the urine quicker.