Board Thread:Lore Texts/@comment-31507215-20170602031344/@comment-29773086-20170602210128

Yes. Quite apart from the extent of what the palantír could do, which we don't know, Sauron was said to show Denethor his armies to make him give in to despair. But Denethor was strong-willed, and so continued the fight, while seeing most of Sauron's troop movements.