I have thoughts and considerations. Not advice, mind you, but considerations for chewing on.
I feel like the chalk test gets the best results for wear (and of course a nice cushy ride to boot), and thus loading (but only at the load at which the chalk test was performed at), however it neglects any research that has been done by the manufacturer in terms of ability to swerve or perform other emergency maneuvers without destabilizing the vehicle too much. In fact, that's why I think the Rebels have such high tire pressures (55 front, 45 rear). They don't have any added carrying capacity over my Express Quad Cab which has (39 front, 39 rear). But they do have thicker tires, which allow for more roll in a swerve, and so they may have increased their stock pressures to account for that. Yes, I know Rebels may be heavier with their ram boxes, crew cabs, and air suspension, but I don't think that justifies going from 39 to 45/55. I think there is some additional reason to justify the larger tire pressures, especially the elevated front pressure, and I believe that reason is stability during emergency maneuvers, which they determined during testing. If that is true, that means stability is also engineered into EVERY truck's tire pressures printed on their door sticker. Going by the chalk test only gives up that stability.
Now, the fix for this is to simply drive more conservatively and defensively, so you reduce your chance of having to make an emergency swerve. But we all know sometimes you can't avoid such a situation, and that is the moment (and probably only moment) those increased tire pressures would save you from rolling, and whatever ill effects may come from that.
So, chalk test is great for determining the best pressure for your (probably) unloaded vehicle, the "light" load condition if you will. But as soon as you add meaningful weight, whether it be passengers, cargo, trailer, whatever, you'd either need to perform a new chalk test at the new load to figure the new best pressure, or interpolate between your "light" chalk test pressure and fully loaded pressure on your sticker (you'd have to know the weight you added), or just jump right up to your door sticker pressures, which do take max load capacity into account, plus stability.
Anyhoo, interesting thoughts.