Very true, neat and short statement. Exactly what one misses on his blog. I think his articles were written mainly for search engines.
The guy is backpedalling in a way from his previous post where he insulted everyone not agreeing with his beliefs.
The arguments were ranging from 'stupid search engine optimizers and total morons' to the more sophisticated ones such as 'incompetent asses and idiots'.

This time his article was more moderate with the simple heading "Why your nofollow testing sucks", where he took a long journey to say that he still didn't believe it.

Interestingly, in another article he states the following: "A good Web site only needs its own internal linkage to help most pages rank for something useful. A bad Web site relies on external links."

Let's play fair here; I understand it was in another context. But he should be aware that the statement means more than he originally thought.

Anyway I don't understand why so much dust around this question.
There is nothing new here, good internal linking was always a kind of "artistic knowledge", with or without rel='nofollow'.
You can dissipate your PR and link extensively all around or you can link smart.
It's your choice.

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Impossible? You just underestimate the time.