ISIS servers don't load balance. this means when ISIS is getting absolutely hammered and ANU's other servers (like WebCT or ANUMail) are free (i.e. not many people are using them at the moment), the strain on the ISIS server doesn't get shared among all of ANU's servers equally. this is why you can log into WebCT or ANU mail instantly, when ISIS is unresponsive.
this is why this happens every freaking time release-dates come by. as stated above it's not hard for ANU to think more logically - release the marks at 4am and therefore the load on the server gets spaced out evenly. people who are eager to check their marks stay up at 4am (the logic behind this is not everyone will check them at 4am) and people don't tend to check their marks multiple times after getting them already; they log in, check them and log out. or an even nicer idea - charge each student $5 or so to get a service where marks get sent via SMS. now that would be 21st century thinking. i know i'd pay the $5 happily.
now to find a suggestions inbox i can send that to so hopefully, come end of the year, my heart won't be racing the whole time the page takes 40 minutes to load.