I can hardly sit through The Two Towers, extended or otherwise, without cringing constantly at nonsensical plot changes.
No, Faramir was not a moody nihilistic relativist who changes his entire outlook without any character development.
No, there was no alliance, and getting from Lothlorien to Helm's Deep in the span of a few weeks, with a full army, is physically impossible even if the army were already assembled. (This was only in the movie after a last-minute cancelled attempt to turn Arwen into a warrior; seriously.)
No, Treebeard didn't spend 2/3s of the book stalling.
No, Frodo did not offer a wringwraith the ring, even for a second. And if he did, there's no way he would've survived afterwards.
And on, and on...