I will totally agree with you that not everyone is the same , nor do all people react in the same way to the same foods etc!
Now to the idea about people with thyroid problems as you mentioned!
Maybe one should consider why these people have these thyroid problems in the first place before making flat statements as one should or should not use kelp?
"IF" one understood that the reason for the thyroid problems in the fisrt place may be because the thyroid is Sick and Diseased because it may not have the needed Alkaline Minerals which it may need to operate properly, then one may be able to look deeper into the problem and understand what may need to be done to correct the overall problems?
So, since these people may have a bad initial reaction to the use of kelp, the question then needs to be "WHY" may this be so!
When you find out that the reason may just be because the Thyroid is Sick and Diseased because it may not have the needed Alkaline Minerals, then the question becomes, what do you do to solve this problem?
"COMMON SENSE" will tell a person that they must find a source of all of the needed Alkaline Minerals for their body to take so as to Help the body to rebuild the Thyroid and other organs of the body!
Now it just so happens that Top Quality Kelp without any fillers etc, may Help provide the body with much of what it may need to solve this problem!
But, as I have mentioned many times for those who have read and understood what I have said, that those people who may be the Sickest, these people may get all kinds of reactions from supplying Top Quality foods to start their body on the road to health, and this is why I have suggested many times for these people to start out slowly with Kelp, to give the Sick and Diseased Thyroid time to start to heal and to then be able to function properly!
Because until you have a healthy Thyroid as is the case with any other organ in the body, you may face all kinds of odd reactions to begin with, but until you rebuild these Sick and Diseased organs, you may not expect to solve your long term problems!
And because it may have taken many years for people to get themself into the Sick and Diseased state they may now be in, "WHY" should these same people think it odd that they are not able to solve their problems in a few days or weeks or months or even years?
And because most people operate upon very short term memory spans, most people are not able to understand these "SIMPLE" ideas of correcting Health problems!
And thus you have all kinds of ideas floating around about what people think may work or not work!
But, for those few people who are able to use some "COMMON SENSE" they begin to see how simple Life and Health really is!
Now to address you many comments about people eating kelp and getting acne from it, because of the supposed iodine toxicity!
Like I have said many times: Not all Kelp is of the same Quality!!!!!!!!!!!!!!!!!
And because Kelp which may not be grown in cold waters or may be grown in waters which may be high in Human waste or other pollution, these and other reasons may be "WHY" all Kelp is not the same and may not provide the same results and "WHY" some kelp may cause the problems which you have suggested!
For when kelp is not in a Complete Complexed Carbohydrate form, like it will be when it is grown properly, then Yes it may have Iodine in a form which may cause problems as you have mentioned!
But, when the kelp is in a Complete Complexed Carbohydrate form, then the Iodine may not separate out and cause these problems!
This is also the reason "WHY" I have mentioned many different times, that "IF" you do not get positive results, then you need to change what you are doing and try something different!
And in the field of food, because of this Very Great problem of Poor Quality foods which most people eat, one must be aware of this problem and not make Broad statements that this or that is so, when they do not know the "WHOLE" "TRUE" story about the condition as may be the case in many of the links which you have refered to!
As in everything one needs to consider moderation in all things!