Many times it is easier to find info once the initial profile for the individual is done. This also gives you a place to put any scraps of information. Sometimes even minor things can make a huge difference. Death, Location, spouse, siblings, occupation, most anything. This gives you a point to collect and share the info with others who may be able to find more.
In the case it is a duplicate, it would just get merged together.
John Thompson literally has hundreds of hits. Was HE in Tennessee? or was it the potential grandparents? Do they have a profile already existing?