Six Degrees of Separation Debunked?

This old piece of news from BBC provides some startling facts which seem to disprove the theory of six degrees of separation. Judith Kleinfeld, a professor psychology at Alaska Fairbanks University, went back to Milgram's original research notes and found out that "95% of the letters sent out had failed to reach the target", "Not only did they fail to get there in six steps, they failed to get there at all." And in another recent study, "only 3% of letters reached their target." Moreover, Professor Kleinfeld argues that "what is more important is not the number of links, but the quality." So, is six degrees of separation a myth?

The study doesn't really disprove the Six Degrees theory. Just because the letter fails to made it in six steps doesn't mean that there isn't a shorter path somewhere out there.

The problem is that we can't see the graph past our adjacent nodes (our friends). We might send the letter in a direction which seems intuitively logical, but in reality is a much longer path to the target. We're really just shooting in the dark.

For instance, if I were trying to get a letter to somebody I don't know in Boston, I'd logically send it to someone I do know in Boston, whom I would surmise would have a better chance of knowing the original target. But it's entirely possible that my friend in Boston is completely in the dark about who to forward to, while my neighbor in California might by random chance know the target.

In order for the study to be accurate, each person would have to forward a letter to everyone they know, who would in turn do the same thing, until the target had been reached. Obviously, any one person can know up to hundreds of people, so it's not really a realistic experiment.