Sears said they had a group of players they where happy with at #47, but when Johnson dropped they had to take him, because he was so much higher in their overall rankings.
So guessing they were targeting another player at another position (guessing the DE Scounton or OT Ersery, who went #48 and #50), but decided Johnson was too good to pass.
He also explained that it was the same with Burke. They traded down in the 5th and he was still there as the clear #1 left on their board, so they drafted him despite having a full CB room.
It’s an interesting info on the draft strategy. The bracket players and draft players in higher bracket regardless of need. It’s what Eagles and Ravens do as well. Need is more cooked into the board in higher rounds. Lower rounds they just stock up on best talent.