This would only work for a Room Only (RO) reservation. It will not work for guests purchasing a Disney Vacation package that includes tickets and/or a Dinning Plan.You can make the reservation for 5 people and pretty much guarantee a day bed room.
That's why parties of 5 get preference for rooms that sleep 5. Would you be OK with not being able to get a room if guests had added Ghost members to their reservation and all the rooms that sleep 5 were gone when you went book the resort?We are a family of 5 and always get assigned a room with a day bed.
Dave