Their OL is pretty much the same from last season, and most of those guys had 2-3 years of experience entering last season. So, there really wasn't much talent left to be developed out of those starters heading into the season. As a result, what we saw from their OL last year, which was decent/average but definitely beatable by good defenses, is going to be about the same we should expect for them this year. Expecting that they are going to be better this year vs last just because of more experience should not be assumed.
Case in point: Kelvin Banks, Hayden Connor, and Jake Majors from last year. We had seen what they were able to do with 2+ years of experience. Did we get anything significantly better from them last year? No, they all pretty much met expectations that we had seen over the previous years. They had tapped into their potential, and having that experience starting only meant that our OL didn't have to experience some growing pains of having new players there.
To sum up my point, no one should expect anything different out of their OL than what we saw last year just because "they have experience." The "experience" resulted in an average product last year, and we should expect average again this year.