I'd expect if we keep 2 RBs on 53, the general strategy would be to keep 2 on Practice squad assuming there are 2 PS worthy.
No team, including GB, saw Crock or Burks as being worthy for their 53, because no team saw them as a late pick or priority UDFA [we signed them for 5K and 1K respectively]. To date I cant imagine Crock or Burks has put anything on tape that has changed their opinion of these 2 backs. We'll get both on practice squad, if they are cut.