From a GA point of view: Eagle flights require us to use a weight and balance check in the operations side of the computer. This takes into account checked bags, fuel, winds and carryon bags that are placed into the hold. When a lot of people check in bags at the TA, we can see how many bags we are able to valet at the gate. If every person does bring a bag that needs to be valeted then checked bags are taken off if we go above the limit. I.E. We do not know that we are overweight until everyone is onbaord.

This route is notorious for it. GA at IAH for 1.5 years.