Maybe his reply was just a poor choice of words? I LOVE my sub-frame connectors. They took all of the twist out of my body over uneven road surfaces, but they certainly didn't make the suspension any stiffer?!?
If your car body without frame connectors is actually twisting (not suspension body roll) from un-even road surfaces.......you better park it.
Anti-sway bars, replacing worn out shocks and worn out suspension bushings help control the body roll.
In my humble opinion, on a street car with street tires, the only function of frame connectors is to add weight. Competition / racing is a whole other animal.
I could be wrong (happens ALL the time....just ask my wife)....so please take my comments for what they are....just us boys BS' n