What I found really interesting was the way in which he engages the results of historical-critical scholarship:
For many even believe—though perhaps with a little too much imagination—that they have good grounds for interpreting the "competition" between Peter and the beloved disciple as an echo of the tensions between Rome's claim to primacy and the sense of dignity possessed by the Churches of Asia Minor. This would certainly be a very early and, in addition, inner-biblical proof that Rome was seen as continuing the Petrine line; but we should in no case rely on such uncertain hypotheses. The fundamental idea, however, does seem to me correct, namely, that the traditions of the New Testament never reflect an interest of purely historical curiosity but are bearers of present reality and in that sense constantly rescue things from the mere past, without blurring the special status of the origin.[That last bit seems to imply he considers the Pastorals -- along with a majority of biblical scholars -- to indeed belong to the second generation. Against a minority view, such as that of Luke Johnson's. Of course, this is hardly to say that the Pope will put these ideas into a model that considers the Pastorals any less normative for being "late" or even an idea that the New Testament preserves evidence the decline and fall of a pristine egalitarian Christianity as it slowly becomes assimilated into a hierarchical, patriarchal Hellenistic culture.] Anyway, as I've said often, I can read anything he has written. There's such richness there!
Moreover, even scholars who deny the principle itself have propounded hypotheses of succession. 0. Cullmann, for example, objects in a very clear-cut fashion to the idea of succession, yet he believes that he can Show that Peter was replaced by James and that this latter assumed the primacy of the erstwhile first apostle. Bultmann believes that he is correct in concluding from the mention of the three pillars in Galatians 2:9 that the course of development led away from a personal to a collegial leadership and that a college entered upon the succession of Peter. 
We have no need to discuss these hypotheses and others like them; their foundation is weak enough. Nevertheless, they do show that it is impossible to avoid the idea of succession once the word transmitted in Scripture is considered to be a sphere open to the future. In those writings of the New Testament that stand on the cusp of the second generation or else already belong to it-especially in the Acts of the Apostles and in the Pastoral Letters—the principle of succession does in fact take on concrete shape.