I don't like to bring fantasy in to reality, but with our draft position and lack of a 4th round pick, it can make sense to draft a round ahead of the other teams and get some of your targeted players. No matter if Zinter had a 4th round grade, with no pick in the 4th you take him in the 3rd or wait and hope you get a 5th round target. If any of you have played fantasy sports, you know what I am talking about.
I think the team sees a potential need for an interior lineman next year and felt it had to get on this year. If Zinter was the next highest graded player at that position, just take him and regroup tomorrow. It's not like a lot of the players we draft from this point forward will even make the team.