I don't think expecting improvement as the year progresses is too much to ask, especially from the #10 overall pick. He has regressed, not gotten better.
Again, it's pretty bizarre seeing all of the excuses made for Rosen. Nothing bad that he does is his fault for some reason. Nick Mullens comes into a similar situation and has shined, won games, and made the 49ers better. But here in AZ, Rosen is doing his best Ryan Lindley impression and everyone is cool with it. He is receiving a free pass and no one, especially the #10 overall pick, deserves a free pass.
But hey, Rosen has grit and whatever