Sail performance = sailing traits ????

I Have been screening some tests on 5-7m, cuddle, sailing boats. Both keel
and centerboard boats.

From what I have seen it looks like the boats that get high ratings for
speed (good sail drive etc) also very often is considered to have good
sailing traits in other aspects too.

Can this be a correct observation?

What is the explanation?

Which is the most important design /solutions? In hull, rig, keel or other
details?

Morgan O.