Originally Posted by JohnShe

Yes, it is obvious that the congress and FAA are using a definition created by the AMA and not civil engineers. But, my thought, which may be flawed, was that if congress read doc 550, the only place where VLOS is used and defined, then congress must have approved of the AMA's safety guidelines for FPV (at least tacitly). And therefore (maybe this is too bit a leap) the FAA has misunderstood the whole VLOS thing by insisting that the pilot operating the aircraft must have unobstructed VLOS. I think!