The chassis sees significant torsional twist especially when combined with higher spring and sway rates. The rockers (which don't have any holes) are what carry that load and prevent a large amount of the structural rigidity. A great example to this is when jacking up a vehicle by a corner before and after installing the connectors. Our subframe connectors tie the subframes in at a second place, adding to the chassis's ability to resist twist. And yes, adding a proper 6 or 8 point cage reduces an even greater amount of chassis cross flex, since you are controlling it on a broader 3 dimensional space.