Was watching HWTB and they touched on something interesting when looking at the final 53... particularly when considering the # of TEs, plus Lupke and some of the other athletic, big frame guys that were retained. They brought up the new kick-off rule... gone are the days of the massive front line blockers with the smaller guys behind them looking for a crease to slip through, now you need guys (across the board) that are big enough to block, but agile enough to shed and change direction quickly.
There is no room for error, if one of these return guys gets a little space... there's nothing in front of them but 60 yards of green grass.