I've lost track of it (especially with the new CBA), but it could be that Hart and Fuld would need to be added to the 40-man to protect them from Rule 5 in the off-season anyway. If that's the case, given that the 40-man was only at 38, there's no harm in adding them now rather than the off-season. This wouldn't affect the option clock, as an option is used by sending a player down, not bringing him up. I do wonder if this is an indication that Guzman isn't coming back this year. Since he's on the 60-day DL, bringing him back would require a position for him on the 40-man, and after these moves there isn't one remaining.