The idea is that since historical facts aren't "science" and they are not "logical" we can butcher them in any way we please -- the author, for example, uses all sorts of statistical voodoo tricks to compress the historical timeline, dropping whole centuries out, compressing several historical persons into one, and generally completely wrecking history as we know it today.
In any case, the whole idea is quack science of the most lowly sort, similar to UFO conspiracy theories and mystical healers. Some of the ideas he makes are so preposterous that nobody in their right mind would take him seriously.
I'm having trouble finding a useful English-language site on the subject -- I guess this will have to do. Don't miss his version of English history, if you have the patience to wade through all of that,