article here: http://www.windsurfblog.de/2015/12/14/speed-day-at-strand-horst/

very happy with my speeds today, similiar wind to yesterday but 4 degrees warmer, which made it a lot more comfortable.

Today I put some more pressure on the lower two battens and used 1cm less outhaul then recommended. Also I used ~4kg of lead. In the end it all helped, got a display max speed of 39,40 kts, 40 kts is on the horizon in Holland :) good week of surfing :)