It is not so much a factor of being lightweight but more of being insufficiently damped.

It is the same with a car that has worn down dampers in its shock absorbers; it is very difficult to keep that car on the road in corners or uneven roads as well for exactly the same reason.

A long hull will introduce disproportionately more damping then the increase in mass-a-top and sailarea. All these dependencies are highly no-linear and that is why so many people become confused when the only look at the specs of boats and not model the behaviour mathematically.

Wouter