A question regarding Ring Featherweight rankings

[Kev]

Why is it that the Ring magazine rates Robert Guerro as the number one fighter in the featherweight division over Chris John?

Given that John is unbeaten and has reigned as WBA champ since late 2003. He holds a win over Juan Manuel Marquez and has made 9 straight defenses of his title.

Guerro on the other hand won his belt 3 years later, lost it only for the fight result against Salido to be overturned because of a failed drugs test on the part of Salido. But there was no doubt Salido won the actual fight.

Since regaining the vacant belt he's made two defenses.

So why is he better than Chris John, surely John's resume is better, at least on paper and even if the Ring don't agree with John's win over Marquez they have to acknowledge it as it was the official result?

Seeing as John beat THE man at featherweight in Marquez this rating is as bizarre to me as if they had Arthur Abraham above Kelly Pavlik in the middleweight rankings