19-0 is awfully high expectations to set.
Obviosuly the great 2007 couldn't complete the task, but keep in mind that even that team was lucky to get out of Baltimore with a win (and Baltimore was terrible that year). I'm not even talking about Rex's time out on what would have been failed fourth down conversion on the last drive, I'm talking about a gift holding penalty that was incurred on Ben Watson on another fourth down on the drive.
Also, please don't jinx us, people felt the 2008 season was also prime for an undefeated season (extremely easy schedule that year too). That year we played the AFC West and NFC West (with both being terrible at the time). Travel sucked, but not the opponents.