I have been taking an average of over 2 times the RDA for about 2 years now and have not had any problems because of it.
According to many vitamin packages, Overdose of iron containg products is a leading cause of death in children under six. Now, I don't know if this means that mulitvitamins have been responsible for such a thing, if so, I would like to see some references. Maybe there are other iron containing products with a lot more iron than mulitvitamins. The FDA is especially hard on dietary supplements, so if there were even the littlest of evidence, or spectulation, they probably could totally ban iron. In fact I bet they have already put some restrictions on the iron containing products, the warning is one example of such restrictions. Anyway, we are not children under six, so that warning does not apply to us.
If there are any references to iron toxicity in adults due to doses near what is in mulitvitamins--post them. I have a feeling though that the iron controversy has something political behind it(like about everything). For example, my mom reads some magazine, I think readers digest. There was an issue disscussing different vitamins and minerals, and iron was brought up, and the end of the iron section of the article section stated do not take an iron supplement without your doctors permission(something like that). I was laughing because we are commonly refered to as "the home of the brave" and we are scared to take iron supplements. By the way, there were no real references either in that article(if my memory serves correct). I'm not saying they don't exist, but I've been motivated enough to search for them. Of iron related problems, one comes to mind immediatly, and that is of an olympic swimmer who was deficient in iron.
Finally, Keep in mind that the information in this post is for entertainment purposes only. Information in this post is NOT intended to take seriously and information in this post may be inaccurate.