I understand I'm changing something by pulling up the board...but am I decreasing resonance because of shorter length, less distance front to back, actual shape...or all??,,,,,,,,,If you want to try something a little quicker, square off the back
of board. Doesn't have to be much, just a small flat area. .............. When you pull up the board you are changing the hydrodynamic resonance
of the board and it stops fluttering.