Very interesting video:
Is that prop really flexing that much or is it an optical illusion?
Digital cameras make propellers look like noodles. Wood and composite props do flex, but not to the extent that it appears in the video.
It's interesting. What does it mean? Just a couple of small places where the air goes turbulent, and then not always? Also, you ever consider doing that further aft, to see what the airflow looks like behind the wing and canopy?
Richard Johnson, EAA #395588