It doesn't do much for lateral stiffness, but it makes the wheel feel faster. It effectively gives the wheel a larger hub flange (though no increase in bracing angle) which means less spoke in between flange and rim to transfer power which makes it feel like it is transferring more power to the road. On the wheels that I've done it to, it hasn't made them more uncomfortable, it has made them slightly heavier and gives me a psychological advantage as they feel faster.