I removed this sentence "Therefore, a strong truth lies in the myth: the faults of the Roman army exposed at Carrhae (such as its vulnerability to cavalry on open ground) were never fixed, and even recurred, as in the much later catastrophe at Adrianople against Gothic cavalry." This is a popular view on the battle of Adrianople but the battle was lost due to the Roman army being halfdeployed on the opening of the battle, not the cavalry. The Gothic cavalry was only lightly equipped and armored, very unlike Parthian cataphracts. Their charge cut the Roman army in pieces as they were out of formation. The rest of the battle turnt into vicious infantry fights, supposedly the Goths using column tactics to further take the Roman lines apart. The Gothic cavalry was only essential in finalizing the victory by hunting down the routers.
The late imperial army of Rome was actually quite adept and varied to face all the range of threats along the long imperial border. This also includes the introduction of increasingly heavy shock cavalry quite like Parthian cataphracts.