RE: First cut on my hunting land...
Having cut my share of hay, I can attest that he would prevent it if he could. A fawn does not do the swather any good and can cause damage and certainly dulls the blades.
As far as timing of when they cut, that has already been covered. As the saying goes, "Make hay when the sun is shining".
As far as a flusher bar.......would create more problems than it would eliminate.