Remember when McD pulled Cook after a fumble at the start and went on to say that he didn't want it to fester on his mind, make him over think/over try and hurt his confidence. He believed it best to work the rookies in slow. I believe that the case with Shakir. I know it sounds backwards, but he's the coach, I am not.
That being said, I think Shakir is gonna be a star for us and have a very high catch vs. target rate. BTW, wasn't Diggs a 5th rd. pick?