I am in agreement with Digger242. I do NOT cross chain EXCEPT when the tire on the equipment does not allow the chain to run straight from the tie down on the machine to the D-ring or chain slot on my trailer.
I try to keep the distance from the tie down on the machine to the trailer as short as reasonably possible. When standing at the back of the trailer looking forward, I like to have chains as close to vertical as possible. When looking at the trailer from the side, I like to have the chains angles somewhere between 45 and 60 degrees. I haul lots of sprayers and combines, which are wider than the main deck on my trailer, making vertical chaining possible.
The D-rings on my trailer are rated for 7500 lbs and the chain slots are rated for 8000 lbs. I usually use the slots whenever possible. Grade 70 5/16" chain is heavy enough for most things I haul--if something is heavier, I use more chains.
We recently had a DOT officer put on a training seminar for our company. The way he explained chaining, if the chain leaves a tie-down, goes through a loop on the machine, and returns to the original tie down point, you can figure the whole weight rating of the chain. If the chain does not go to the same tie down point, it only counts for half of it's capacity. In this picture, if I understand the rules correctly, the chains could only count for half of their rated capacity.
I will try to remember to get some pictures of how I chain things down, now that I have a phone with a camera that works.