My reply was not meant to address the "point" of the question. Since I believe the point being "whether or not this situation is or is not a control group" had already been wonderfully explained by MR and JAY21, I just thought it would be helpful to the viewers out there to give an answer to the specific question of "do you allow this couple to establish separate plans?". I wouldnt want anyone to walk away from this thread and think that from a technical point of view that because it is a control group, the husband & wife CAN NOT have separate plans.