I am reading Andras Frank's Connections in Combinatorial Optimization. On the Page 34, the description of how to use the Replication Lemma to prove the weak perfect graph theorem seems only to prove that there must be a largest maximal stable set intersecting all largest cliques, if not, a contradiction occur. I think that there are some more steps are needed.

I have understood the proof in Frank's Connections in Combinatorial Optimization.It is interesting that how natural about the combinatorial proof.