Sure, they now have the game film to prepare for him... whoopty. I would think we are improving as well to still throw kinks in the competition's preparation. (re: OL additions, revised blocking scheme).
Plus it's been noted that DD has a knack for seeing the split second hole and hitting it unlike previous RB's that couldn't make the decision fast enough. Also, for a change of pace and style, Hollings will come in.
So to answer ya, DD will get through... but will also get hit. He and Hollings has the chance to tear up mid-field (DD's breaking tackles, Hollings speed) If it doesn't happen... yeah, we may become one dimensional for THAT game, but we have improved recieving targets as well. Finally, Hollings will get a shot - defintely.