The so-called "Jesus Seminar" was a bunch of liberal theologians who made their decisions based on popular vote. If they "didn't like" what Jesus said, they just dismissed it as "inauthentic." Their procedure was really no more sophisticated than that. They actually used coloured beads in a jar to decide whether or not they liked particular sayings.
No textual critic accepts the pronouncements of "The Jesus Seminar," and their pronouncements have been taken seriously by no reputable scholarship. Today, they are a kind of anecdotal joke about how silly liberal theologians can be.