Any time a team has to depend on a rookie player to fill a position of need, a weakness has been identified by all opponents for the upcoming season.
Any time you start a rookie you are putting a player on the field that has never experienced the speed of the NFL game, he is overwhelmed by a veteran opponent. Any rookie not drafted in the top ten has areas in his game that needs improvement in order to prosper as a starter.
One preseason isn't going to polish an offensive lineman and we saw Tyler Smith struggle at times, no criticism intended, he will get better quick and he will become a very successful player for us but starting rookies along the offensive line is dangerous unless they are the 2nd coming of Larry Allen.