Torsional rigidity is the name of the game. Round tubing resists
twist better than square designs.
There's some truth to the statements provided on US Car Tool's site,
they just don't tell the complete story.
ex-Global West GM
As the drill sergeant said, "I taught you everything you know. I didn't teach you everything I know."
"Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so."
- Douglas Adams