Wouter you keep saying that a fully powered up M20 without jib would be slower than a fully powered up M20 with jib around an upwind/downwind race course, but you have no data to rely on. Finishing times for the M20 on the last two Round Texel doesn't say much when you are looking for these small differances. The only relevant data I could find was the upwind leg on last Texel, and that showed a small advantage for the uni rigged M20.

The only way to prove which version on M20 that is the fastest is an upwind/dowind race.

/hakan