I really love Jackson's work in FOTR (that's an understatement, really), but this quote really has me scratching my head. It strikes me as ridiculous.
We have the Ents and Isengard, Theoden's epiphany, Helm's Deep, and Frodo and Sam making about an inch of progress on the map.
With the exception of Isengard, there is little closure on anything. Nothing that has a direct impact on the outcome of the story really happens in TTT. TTT is the white filling between the cookies.