False positive? What is the rate of misidentifying two people who look alike as being the same? How do they plan to deal with this? It could be seriously problematic for the victims of such a mistake, worse than erroneously being on the no-fly list.
There was a report of twins applying for a learner's permit at the same time running into problems, so this can happen.
Applying for a second license under a false name seems to happen when the first license has lots of unpaid fines and/or the license is revoked. So if A has a perfectly fine license, and B applies for a license and happens to look exactly like A, this would look a lot less suspicious. Should be fine to give B his license and then investigate. On the other hand, if A's license is revoked, then this is more suspicious and more risky. The first idea would be to contact both A and B, and if they can both be contacted, it should be possibly to prove they are different. If A cannot be contacted, that makes it a bit tougher. You would ask B for evidence that he has existed for some time.
There's a difference to the no-fly list: That gets people into trouble at the airport, with very little time to sort out any problems.