I agree and the center position is crucial...any time the teams starting center is out DO NOT bet on that team...teams usually have either a great run blocking O-Line or a great pass blocking O-Line, it really is built on the teams strengths,,,,
The Ravens for example when they had a great O Line, were a tremendous run blocking O Line but were just average or slightly above pass protecting and that became their big problem once that line started getting older, they simply could not pass protect at all the past couple years, even LT Jonathan Ogden had a lot of trouble againt the smaller pass rushers who ate him alive out there at right end. .
the Steelers have traditionally had great offensive lines, the Dallas teams of the 90's were incredible , Miami and Oakland in the 70's and also New England .