Did Gandalf make a mistake at Isengard ?

[Hakon]

Originally Posted by The Mouth of Sauron

A Nazgul could have snatched them easily enough, as they sat alone by the gate, while the Ents were working at the north side of Isengard.

I think even the Nazgul fear the Ents, they would not venture towards Isengard if they were aware of the Ents there.

[William Cloud Hicklin]

A Nazgul could have snatched them easily enough, as they sat alone by the gate, while the Ents were working at the north side of Isengard.

Flight time from Barad-dur to Isengard was six or seven hours. It wouldn't have been, as they say, actionable intel.

And that assumes that Grima even was concerned with anything other than the political disaster at Edoras and Theoden's riding to war, as well as the destruction of Isengard. Shock upon shock: Gandalf not dead, Isildur's Heir revealed- what matter small rag-tag and bob-tail? Heck, was Wormtongue even in the loop regarding Halflings and their significance? He was merely Saruman's mole in Meduseld with a Rohan portfolio; Ring-related matters were not within his ambit of need-to-know.

And why would Saruman have done anything of the sort? "Sauron, sir! Halflings right here! Maybe one has the Ring!" Saruman was not about to tell Sauron anything Ring-related if he could possibly help it. He was playing a double game right up to then end.

[William Cloud Hicklin]

So, in Tolkien's own words, only Saruman had much interest in, or knowledge of, the Stones and he never mentioned them to other members of the White Council. In other words: Gandalf probably did not know about the Orthanc-stone.

I would also mention Denethor's words, "Though the Stones be lost, they say." It's of course a freighted line, because Denethor knows they're not lost, and Gandalf knows they're not lost, and they each don't know, even if they may dimly suspect, that the other knows the truth. Nonetheless: "They say." In other words, the Conventional Wisdom was that the Palantiri had all disappeared.

[Ibrîniðilpathânezel]

Originally Posted by William Cloud Hicklin

In other words, the Conventional Wisdom was that the Palantiri had all disappeared.

Except for the one in Elostirion, if I recall correctly. Though that one was not useful for anything but looking to the West, also IIRC. I think my brain is still post-vacation addled....