I wouldn't say you will need them, no. Depending on the size of your tank, i think some type of dither will make an exellent addition for a solo pair. Personally i'd run with a hand full of Silver dollars with Dempseys. As stated dithers are commonly used to bring the personallity out of shy cichlids, the reasoning is that if the shy cichlid see's that the dithers are not scared, then they themselves have nothing to be affraid of. They can also be used to help a pair to form a strong bond, instead of beating on one and other. IMO they also add that little extra flair to a tank.