I wasn't aware of that. As an engineer, I'm not sure what difference it would make. SCCA requires that diagonal. NHRA doesn't. The idea that the main hoop would skew laterally in a crash with the back bar and #7 & 8 bars in place is pretty amazing. NHRA uses SFI for testing. I'm not sure who SCCA uses, but I trust SFI to put our blueprints for cages that would survive almost anything, per speed spec.