In the article, Evolution of Wright Flyer Propellers between 1903 and 1912
By Robert L. Ash, Stanley J. Miley, Drew Landman (see
http://www.wrightexperience.com/indepth/pdfs/props.pdf )
, the authors, components of the Wright Experience team that replicated Flyer I 1903, wrote:
"However, their methodology is not even mentioned in contemporary literature, even though they (the Wright brothers) were achieving propeller performance levels by 1905 that were only achieved by others after World War I."
The citation is another argument the two brothers lied about the performance of their 1903 - 1905 propellers as long as after Aug. 8, 1908 their planes and propellers became known, they even started to sell them. Despite many plane builders being able to study these miraculous propellers nobody was able to replicate their claimed high efficiency till after WWI! This is ridiculous.