This would be a very salient point, in the context of this thread.MrMacSon wrote:his account of the Jewish War is not based on Flavius Josephus.
What you have highlighted does not seem to contradict the point I've made in this thread (which is that a name would most likely have been used if it were known as the name...). Nothing speaks to an attempt at precision or accuracy in your quote (except, as it so happens, positively, in parts not highlighted, from the very same quote... "maximum chronological clarity," "his information about the campaigns themselves appears to be comparatively accurate," "wrote letters to people who could tell him more," "pretty accurately renders a speech by Claudius").
We should be careful about reading anything into the statements made by secondary sources when they may be emphasizing quite different aspects (than that which we are interested in) based on different evidence (than what we ourselves our interested in). And we also of course must be especially careful about any very glittering statements or sweeping generalizations in secondary sources generally ("not a real historian," for example, whatever that means). A slightly better way to understand this paragraph and its emphasis, if it is accepted in the first place, would be....
This brings us to the vexed question: what sources were used by Tacitus? We know that he wrote letters to people who could tell him more - two letters from Pliny the Younger, concerning the eruption of the Vesuvius, survive - but he must have used other sources of information as well. He pretty accurately renders a speech by Claudius, which has survived as an inscription. The idea that he checked the state's archives, has by now been rejected; and he sometimes quotes authors like Pliny the Elder. Still, it is remarkable that he was capable of ignoring important sources as well - his account of the Jewish War is not based on Flavius Josephus. Essentially, Tacitus' sources are an unsolved riddle - which is less surprising than it seems: he was not [primarily] a real historian [as his purpose for writing], but a moralist.