True, but if it saves you an extra machine & labour unit it can be attractive. (Kinda like a Lexion... )
And that’s before you have the buffering capacity in the field if a truck is late back from the silo or at night you can fill while trucks wait in line overnight, w trucks unloading in the morning while everything else gets grease/fuel etc; generally set them up on a paddock road/hard area and the trucks just come in, turn around so they’re ready to exit, load and are gone.
Little different harvest here than what you may be used to. For me the large cart is my buffer and trucks have a 1-4 mile haul to a 16" auger with no line-up. The weak link in my operation(especially when running two large combines) is unload speed on the combines. Quick turn-around times are key at every level.
But I could see how the mother bin would have a smoothing effect if the truck return times were less predictable.