Please read again my post from here:
The Wright brothers just glided in 1903. They flew in 1908.
Do I have to repeat 100 times that the Wright brothers claimed they had obtained 66% efficient propellers, they built them at this efficiency. They did not just estimate a 66% efficiency for their propellers!
I re-read your post and it is very difficult to understand. Please re-explain it to me like I am a very teachable 5th grader.