This seems misplaced. My understanding is in most of the western world, architects can't actually design buildings anyways. They would need a PE for that, which

This seems misplaced. My understanding is in most of the western world, architects can't actually design buildings anyways. They would need a PE for that, which they may not have. So instead they work with engineers and the process may more or less go as described. I have seen plenty of buildings that had last minute changes made, including jackhammering through the floors the minute the concrete had cured.