That 1 comment raises very serious doubts about that paper. The paper is basically assuming that a polynomial time solvable problem takes super-polynomial time. If it's using that fact in an integral manner then that kills the proof. And even if not, just the fact that the paper is making such a basic mistake raises questions as to how solid the rest of the paper is. Also the guy who made the comment (Luca Trevisan) is a very famous researcher in theory/crypto...
