Bureaucracy becomes significantly easier to navigate once you realize bureaucrats are human beings and if you send them an overwhelming amount of documentation they'll often decide they don't get paid enough to go through all your bullshit and it's easier to just give you what you need
There's also the additional aspect that many bureaucrats don't actually have any personal investment in whatever is going on, all they care about at the end of the day is that protocol was followed and their ass is covered and by sending them a pile of evidence they'll often feel more comfortable that their ass is, indeed, covered