I'll try and answer some of your input/questions. In the most recent case of "rudder lockup" I had both boards down (seems to ease helm, but maybe not?) main traveller cracked off slightly. All main and jib telltales flowing nicely except the very top of the jib was venting some air from twist and my jib trimmer tends not to keep up with my ancient surfer driving techniue. One problem is the daggerboards are very thick, might that be causing cavitation all the way back to the rudders? I think cavitation was definetely a big problem with the old thick rudders. I lengthened the nacra rudders to make them deeper because of the higher/deeper transoms of the reynolds. I have heard of this problem with the boat before, some dudes in santa cruz got "locked in" and were stuck going downhill for miles in heavy air. The problem only seems dangerous when I don't cleanly slice off the top of a breaking wave and it wants to drive the lee bow off when I want the boat to s-turn down the face and through the trough, or when I might run out of sea room. It's never been a problem when going to weather, feathering in big puffs etc. thanks for our consideration. p.s. I've driven a new reynolds 33 in similiar condtions and it is very very sweet and very very fast.