I cross mine as prescribed by so many over the years. Just seems to make sense. The puzzling part is that so many trailers have the connection point on the trailer A frame so close together that it's doesn't really seem to matter if they're crossed or not. One would think to be effective as a cradling system the connection points would be welded farther apart to make a true "basket" under the hitch.
Im also a believer in having the breakaway switch tied directly to the truck frame as a last ditch effort to stop a loose trailer. If it falls off the ball down onto the chains the truck should still be able to control it to a stop. I don't want the breakaway switch in the emergency loop until, well...it breaks away!