I just realized I never thought about why System.out.println doesn't declare an IOException. Turns out PrintStream silently catches the exception and turns it into an error flag no one ever checks. Undermining both the Ability to handle IO errors using exceptions and making it impossible to find out what happened over what I assume was the ability to call System.out.println without checking for errors. Right now I am just happy that my IO code generally writes to binary streams so I don't have to rush through my code base to check for that nasty surprise.