Replacing 3/4’s of your starting Secondary is difficult to do in one offseason. Now, the Eagles have to replace 4/5’s of it after trading Brandon Boykin to the Steelers on Saturday night.
The Eagles essentially considered Boykin a starter because the slot CB position typically plays ~50% of the defensive snaps throughout the year, maybe more. It’s not as if the Eagles are replacing a backup here, so this move should not be taken lightly (not that it is).
When Kelly took over as coach in 2013, he replaced 3/4’s of the Secondary then as well and that turned in mixed results.