That would presuppose that they were put back on the field by Fisher before they had completely healed. Risking both their long term and short term future with the Rams and in the NFL. While I don't know if that is correct or not, I chose to believe that neither they nor Fisher would risk that. You're healthy enough to play on special teams and do spot relief of Wells (Barnes) but not healthy enough to play the position during the rest of the game/season? Not buying that.
Furthermore, subsequent events have proven my contention to be correct. Of those healthy enough to play last year, only Barnes is still on the team and in addition to not being able to beat out Wells last year, he hasn't shown that he's anything but marginally better than Rhaney and Jones in TC and the preseason this year. As I've said before and as I still say, I feel that Barnes is merely the lesser of three evils.