When I was trying to get Bills@Phins tickets this morning, they kept giving me a "tickets not available in that section at this time" message. After about half an hour, I got 2 tix (sec. 446, row 29, seats 15 and 16, stop by and say hi!). I don't think they have a separate message for "site is jam-packed, come back later", so I'd just keep trying.