AD455 - the fall of the Roman west?

[Nathan Ross]

Drinkwater, "The Alamanni and Rome," 327-329. The evidence says the local Limitanei garrisons from roughly Mainz to Pannonia Prima were intact

Good to know - thanks. I read Drinkwater several years ago, but my interest at the time didn't extend into the 5th century, so I skipped that part...  It does appear that he says the Rhine garrisons lasted into the 450s, or until the death of Aetius, at least - no doubt some sort of garrisons continued under Aegidius, although determining the difference between 'Roman' and 'barbarian' would be tricky (and the barbarians could still claim allegiance to Rome, of course).

an absolutely exceptionally competent and capable leader, Aetius

Well you would say that!

a growing rift between the Gallic and Italic aristocracies (which ended up in Majorian's assassination)

What's the story there? I thought Ricimer was behind it?