I think it depends in large part on how you fill out the top part of your depth chart ROSTER. If you grab solid, steady reliable players as your RB2 and WR2/3 (guys like McGahee, James, Driver, Ward, etc), you're probably have more wiggle room to swing for the fences with boom/bust types with your late round draft picks. And if we don't work out, then you can toss them to the waiver wire during the season.
However, if you roll the dice with a risk/reward type as a starter (Benson and Jacobs come to mind, Colston, B Edwards, Peterson/Lynch etc), you may want to rein it in with a backup who, if your higher pick falters, can still provide solid, unspectualr nuimbers to keep you in the hunt. If your starter bombs, and your home run late pick flames out too, then you're in big trouble.