Mostly because all the other VWM Blades were sailed doublehanded and had more gear on board. Hans also sails with a few modifications like dyform rigging, carbon boom and carbon spi pole, I believe. The remainder is caused by the weight difference between the carbon and alu masts. Hans boat is a 2007 VWM Blade and the others of the some production series were around 110 kg in 2-up. Basically this means a 6 kg difference in weight. Not too unrealistic with a carbon mast, absolutely no jib gear and some small mods here and there.

But like you I don't really understand why there was a similar difference between your Stealth and Hans Blade. Afterall, your boat is a fully optimized singlehander as well with carbon boom etc. There shouldn't have been 8 kg difference there.

Wouter