It'd be great to stumble on to another Ratliff-level superstar in the late rounds who's quality from day 1, but it's not like that's a regular occurrence across the league. Seattle's recent drafts have had plenty of misses high and low. Same with Washington.
That all said, Dallas does seem to focus on utility players on Day 3 - 3rd/4th CB, 3rd/4th WR, 2nd/3rd TE, FB, special teamers. DL seems to be the exception -- Lissemore and Brent.