Wouter,

we are about to cross over into a whole different subject, worthy of its own thread. "Fads and rages in catsailing". There have been plenty of such things that have come and gone. In the A-class canted hulls and canted daggerboards was all the rage for some time. "Everybody" wanted them. After a season or tow, the trend dies out becouse it usually is not as effective as claimed. I could mention other examples from the Tornado class, but rules like the "15mm" rule is stop teams from experimenting with them. Top teams do play pranks on each other and the competition by doing things like this.