| Quote #1
Neither Pippin nor Merry remembered much of the latter part of the journey. Evil dreams and evil waking were blended into a long tunnel of misery, with hope growing ever fainter behind. They ran, and they ran, striving to keep up the pace set by the Orcs, licked every now and again with a cruel thong cunningly handled. If they halted or stumbled, they were seized and dragged for some distance. (3.3.63)
Poor Merry and Pippin are such youngsters, and in many ways they are the most vulnerable of the company. That makes their current situation all the more heart wrenching. Sure, they have traveled with the Company for many weeks, but they still have no experience to prepare them for this brutal forced march and the suffering that's raining down on them. Don't worry; they'll prove their mettle.
| Quote #2
It is said that the Hornburg has never fallen to assault [...] but now my heart is doubtful. The world changes and all that once was strong now proves unsure. How shall any tower withstand such numbers and such reckless hate? Had I known that the strength of Isengard was grown so great, maybe I should not so rashly have ridden forth to meet it, for all the arts of Gandalf. His counsel seems not now so good as it did under the morning sun. (3.7.134)
Théoden is great when he has lots of things to do. He seems happiest when he's galloping off at the head of his company of soldiers. When he is stuck sitting inside the Hornburg trying to think about defense, he has time to start worrying and fretting. And, if we may say, he's a little prone to despair. Théoden has to bear some lasting effects from Wormtongue's influence, and it's a common theme of The Lord of the Rings that you can't just erase suffering as though it had never been, though you can usually heal the worst of its damage.
| Quote #3
"I think all will be well now," answered Gandalf. "[Pippin] was not held long, and hobbits have amazing power of recovery. The memory, or the horror of it, will probably fade quickly. Too quickly, perhaps." (3.11.63)
Pippin is so shaken by what he sees looking into the palantír that he can barely talk about it. Sauron hurts him, even through a glass ball and from a great distance. But Gandalf comments that the memory of it will leave no lasting injury, that it will fade too quickly, perhaps. Does he mean that Pippin won't learn a lesson from this experience with the palantír, that his suffering may pass too quickly to teach him anything? And does that mean that Pippin needs a bit of suffering in order to learn a thing or two?