lol, I may be a big dork, but I'm not crazy. The earliest I've gotten to Comiket was 8:00am. I did notice it made a difference, but unless you have someone to talk with for the next 2 hours it'd probably get annoying.
I usually shoot for either 9:00 (if I'm feeling dedicated) or just say "screw it" and show up at 11:00 to avoid the line. The line certainly is an experience everyone should have at least once though. You certainly never forget it lol.
Summer Comiket 90: Tokyo, Japan
Military Odyssey: Detling, England