odds are you're not getting another starting rb at the slot where sproles would get drafted, so that analogy is not a valid one. Asking if sproles would be a starter for you if LT went down is a very valid question, however. This is always the key when deciding to cuff. In case of sproles, its a borderline case, because he is fairly explosive, but would he be the primary rock toter? WOuld he be able to handle that load? What about Hester? These questions lead you to believe he won't be worth much if LT went down, thus I wouldn't cuff him. Instead, I'd opt for a ray rice, or one of the many other backups that were drafter later in the draft that you could see starting in your lineup if they became the starter due to injury of poor performance by the guys ahead of them. Too many rookies fitting that bill this year to waste time with sproles IMO. Now all that goes out the window if you're doing auction ofcourse. There the price might be right to stash him away on the bench...