Whether the vehicle tie downs are crossed or uncrossed doesn’t matter when it comes to load shifting.. If one side breaks, the other side can become slack. It’s just which way that changes.
Disagree especially depending on the situation. If you have fairly short front/ rear ties, and one breaks, the load cannot shift very far simply because the straps/ chains are so short. But long crossed chains can do anything, an JUST ONE TIE can completely release any effective tie
Picture this..........Car is strapped crossed front and rear. One strap, front or rear becomes broke/ loose, whatever. The remaining strap can allow the load to "waltz" to one side which causes slack, and THEN it can move forward--in the case of a loose rear tie, and THEN the two crossed front ones don't have any control, front/rear/ side/ side.
You want SHORT ties front to rear. You could break one or two on one side, and the remaining two would prevent front / rear as well as excessive side-side movement.