My guess is Iowa wants to lock things up ASAP considering they were successful holding on to nearly all early verbals last year with that approach. Allows them to spend more time strengthening their position with them vs. running around the MW playing musical chairs with other programs for the undecideds. I would think it's first come first serve with most positions including RB. Some reporting we're trying to flip a fella we were after earlier, Michael Warren, a Kentucky verbal. Looks a lot like a Benjamin type RB. I doubt Iowa has lost interest in Benjamin but have to hedge our position.
I also don't see Ferentz pulling an offer on a verbal as a general practice if someone better comes along later. I think the earlier approach to filling the spots serves Iowa best as we aren't noted for our closing power in the late innings especially when competing vs. the Power 5's.