here are 2 videos that I just recently saw posted at the Yahoo Sunfish Sailor Group about modifications to make your hiking strap have some ability to adjust the tension on the hiking strap while sailing.
in this first video, Dayton Colie goes into a little detail on how David Loring, the 3-time Sunfish Worlds champion, customizes his hiking strap to give him to capability to adjust the tension on the hiking strap while in the middle of racing out on the water. it does involve making a custom attachment using webbing material and some grommets.
Dayton Colie and David Loring collaborated to make a pretty sweet DVD called “Back to Basics for Sunfish World Championship Speed” – it’s available from most Sunfish dealers, including Intensity Sails. the video could stand to be updated for HD, but it is still a great video, with rigging tips as well as tips for while out on the water.
in the second video, Eduardo Cordero and Paul-Jon Patin display some what their sailing coaching school, Starboard Passage, has to offer. the hiking strap customization is at about 0:55 with more comments throughout the video about it.
there are also a ton of pictures on Sunfish rigging at Starboard Passage.