Not everyone can be an airline pilot now matter how much they want to be.....Afirmative action only goes so far.
Before you take him up for a lesson, sit down with him and go thru the motions on the ground. Ive had students try to do a lazy 8 or a chandelle and it was like no one was flying the airplane. It turned out these students did not have a clear picture in their head of what they were supposed to be doing. Ask your student to talk you through a landing and ask him questions along the way. When he says its time for flaps, ask him why? Is he doing it by rote or does he understand that when the flaps come out, the plane changes aerodynamically. He may not have a complete understanding of why he is doing things.
Also remember, that if you sign him off you are responsible for him. I had one student I just would not sign off as I did not want the FAA and lawyers looking for me.