Joining by IP should not take longer than joining through the Master Server should. If nothing is coming up when you try to join by IP, then nobody is hosting at that IP, and the screen will remain black until someone from that IP decides to host. Trust me, I've joined by IP before. Basically, the Master Server just serves as a graphical interface that lists certain public online games. When you join them, it's still going through the same procedure that it does when you join by IP.