We had great wind yesterday and the water was quite flat so all good for some overpowered slalom blasting. I rode my 6.6 Ka Koncept with 104 falcon/36 fin. The big guys were on 7.8 Reflex2's and a Vapor 7.6. Anthony took out a Gaastra Savage 6.7 and smoked everyone.
Two problems arose amongst the guys which require some discussion.
The first problem is hand and arm exhaustion which caused Andre (a heavyish intermediate sailor) to have to take frequent rests. Despite the fact that we are hooked in, there is always a tendency to pull on the boom with the hands as well. This happens more when we are overpowered and in survival mode. The result of this is that we become exhausted and our sailing suffers as the session progresses. Another reason for this pulling can be that the harness lines are incorrectly sited causing us to have to pull on the back or front of the boom to compensate. I eliminate both of these things by periodically releasing one hand from the boom while blasting along. This shows me that the lines are in the right place and also reminds me to use the harness hook/lines and not the arms to counter the rig. I read once that you should have a feeling of playing a piano on the boom arm while blasting along to get yourself to release the deathlike grip. Easier said than done when you are out of your comfort zone but something to try from time to time.
The second problem mentioned yesterday was the front foot wanting to slip out of the foot strap while blasting along. At least two of the guys mentioned that this had been an issue. The conventional wisdom is that you should release a bit of outhaul and lower your boom slightly to correct this problem. I found that using a slightly less aggressive fin makes a difference as well but have never read anything to corroborate this. When I was testing the new deck on a Falcon prototype I put my 41cm Select RS7 fin into the board and, with my 7.8 Ram found the thing almost impossible to sail. My front foot simply refused to stay in the strap. As soon as I changed to an Evo Lightning (softer and more raked back) the problem disappeared. The condition was also less noticeable when I screwed in a 37cm SL7 fin (a drop of 4cm in fin length). So my own experience suggests that fin size and shape also has an effect on front foot lightness but you need to experiment for yourself if you have this problem. It could be your board telling you that it is not as fin hungry as you think.
I will get round to discussing rough water gybing one of these days.