I am reasonably but not totally happy with it I feel that it is slightly unfair to the subject since it implies that this is merely his estimate His estimate would seem to derive from the estimates of others so I am not sure why it needs to be described in a way that implies it is quite this subjective Personally I dont believe it is even necessary to state a number in the opening line I would suggest something such as the following Christopher Michael Langan born c  is an American autodidact He is wellknown for claims by himself and others that he has scored extremely high on IQ tests Billed as by some accounts the smartest man in America etc Possibly this is not perfect either