It's like we don't remember what we just went through in rebuilding the OL. The team brings in value VFAs (Mack, Livings, Mincey, McClain) who can hold the fort for a year or two, and looks to draft young talent to develop. They take fliers on young guys they think might develop into rotational players, or who might have the ability to become starters for you down the road (Nagy, Costa, Leary, Coleman, Bishop, Gardener). They sign talented priority draft picks (Smith, Frederick, Martin, Lawrence, TBDs). They take flyers on high-potential veterans with injury risks (Waters, Spencer, Okoye). They see what pans out, and then fill in the cracks.
Most of this time, we haven't had an embarrassment of cap space (I don't care what posers want to pretend they heard from other unnamed posters, the CBA lowering the expected cap and the penalty from the Austin contract caught us by surprise and hurt our ability to maneuver in VFA the last few years). So, we may look to add an impact player on a long term deal on the DL if there's a good one available, though I hope we resist that temptation.
Also, we possibly would have drafted a DL in either of the last two years (personally, I think Aaron Donald and Sheldon Richardson were probably targets in each of the last two drafts and, without the benefit of hindsight, each were better value options for us than the guys we ultimately took). It's not like we're not looking at upgrading our trenches. There's a very real limit to how much can be done during the process of retooling an entire roster just from your regular allotment of draft picks without the aid of stockpiled resources, an abundance of good young talent on your 2010 roster in the first place, or any reasonable cap room (other than what we overspent on Carr) to speak of.