I think that's a pretty harsh assessment of Sims, and one without much merit as far as I can tell. I don't have access to PFF rankings, but from what I've seen in the past Sims has always graded out very well. I can't recall right off the top of my head, but it was either 2011 or 2012 that he graded out as the 4th best left guard in the league.
Maybe I'm missing something, but Sims has been pretty damn solid from what I've seen...
I don't get it either. Sims has been a solid pice of the O-line. He was the first real piece we added that made our O-line start to get better.