It doesn’t. It thinks it needs that much space, but it doesn’t actually want it. It also has issues with correct drive scanning/detection and detecting a moved/partial install.
SSD’s… sure, you get a nice bump in loading times and what not, but they are not recommended purely for that fact that the DevKit can be write intensive at times, not to mention it will continuously grow in size regardless of updates… I think one of my DevKit installs is sitting at 150GB’s or something.
-WM