On offense far more than on defense, you need to have all hands pulling the same direction. Although they may all be talented, and incongruous OC and QB and O line spells a sputtering offense. Talent needs to match scheme, and you need a healthy dose of good luck staying injury free.
A successful O Line is an uninjured one. Doesn't even have to be the best guys, but they need to stay intact, as was stated above. Cohesion is everything, especially if they are a physical match for the type of offense called (ZBS vs power man, etc).
Our most successful season in the Warner era featured guys starting on the line like Lyle Sendlein, Deuce Lutui, and Mike Gandy. None are hall of fame types, but that season they all stayed healthy and started the whole year.
Do you think that Humphries, Cole, Barksdale, Pugh, and one monster guard addition could form a solid line, if they stay healthy?