The Nazgûl's Powers

[Attalus]

At Valandil's request, I will lead off with this question: what do you think that the Nazgûl could do? I mean, offensively, martially? My sig quote says what I think and why I believe it. JRRT goes on to say (in that Letter) that this is before Sauron added demonic power to the Witch-King, right before the Battle of the Pellenor Fields, which explains why he was able to shatter Éowyn's shield and break her arm. Before that, the Nazgûl seem rather ineffective. At Weathertop, Gandalf and then Aragorn are able to drive them off single-handedly, Aragorn with the feeble help of the Hobbits. They were able to scatter the Dunedain at Sarn Ford, but I suspect that they bolted because Aragorn was not there, in very fear, and a running or cowering man is an easy target for a backstab. All they could do to poor Frodo is stab him with a knife, when surely nine beings like the Witch-King in the Pellenor would have just killed them all and taken Frodo with them. And what about the Prancing Pony? Why didn't they just storm the place and take it? True, Aragorn was there, but he was only one man and they didn't know that, anyway. Think of the burlesque recorded in "The Hunt for the Ring" with the Nazgûl, including the W-K, blundering abou the countryside, looking for the Shire. Even then, the best they could do is terrify the Southron spy and Wormtongue. Saruman made fools of them. Well, there is the gauntlet.