I can't remember if I ever posted a Black Grouse lekking video - given the issue I have had with file selection. Apologies if I have duplicated
https://www.youtube.com/watch?v=XqsafXySUzA
Think that you did Bob cos I remember commenting that their movements reminded me of fencing moves, en garde & touche and all that ... no harm in seeing again though cos it was a while ago!
2013 photos & vids here
eff37 on Flickr