I got proctor spreader arms (fully adjustable) and have 50 mm spreader rake and 20 mm prebend. I've set it up for doublehanded sailing so I may be sailing with to little prebend for singlehanding however I seem to get it close enough to where I want it by using the downhaul and mainsheet together. I can go from full mainsail to totally flat by setting the right tensions on both the downhaul and mainsheet. In this respect I have no issues with the mast being either "too stiff" or "too flexible". Of course the right mast rotation setting plays a role in this as well.

With regard to adjustable diamond wires tension. This is allowed under the F16 rules, you may build yourself a system that allows you to finetune the diamond wire tension WHILE sailing. When we first drafted the class rules I felt that such an allowance would be a welcome one later on. That was 5 years ago.

Personally I feel no need for it as I'm finding that I win far more by getting my head out of the boat and concentrate on sailing. I'm not adjusting the outhaul and stuff during racing anymore. It is just too much work and you gain alot more by just nailing that mark rounding, hook on quickly and get on your way on the new heading as soon as possible. even if the such secondary settings are slight off the optimal. After a few months experimenting I've found a decent prebend and diamond tension setting and I'm running with that now. Dirk, maybe you should do the same, invest soem time in finding a good average setting and then run with that.

Wouter