The following are a list of Coaches on Youtube that I have learned things from. The best ones are the last three.(also FREESTYLE videos). If you have a few hours browse away!
Peter Hart - old video https://youtu.be/EwfZB4CQ3hw
Light Bulb:For light wind, weight on the front foot when sail flip to prevent rounding into the wind. I thought rounding up was somehow related to sail position.
Windsurf Coaching - Colin Dixon
Videos of COMMON MISTAKE; https://www.youtube.com/channel/UCpLl_R7IQnV2JgSlVcpkQfQ/videos
Other good videos from him.
https://www.youtube.com/results?search_query=TWS+tenerife
Light Bulb: Balanced point. Light Wind Core Skills #1 (Must Watch).
https://youtu.be/VK_wQcI3_C4
Sam Ross - I like the emphasis on highlighting key points. He also has a windfoil series.
https://www.youtube.com/channel/UCyFxqjzH4U7q6I4-4rV3HvQ
Quick tip series:
https://www.youtube.com/results?search_query=starboard+windsurfing+quick+tips
GetWindsurfing - Phil Richards & Danielle Lucas
His most recent series: Windsurfing at Home highly recommended.
Light Bulb: HEAD position of the board before and after the transition for the tack; and STEP to back of the board.
https://youtu.be/1OQuOQq1v78
https://www.youtube.com/user/GetWindsurfing