What can I say? I would say you're probably right. Case in point is George Lucas' The Phantom Menace. Straight, unadulterated Star Wars from the creator himself, who is a film-maker. Universally despised upon release.
But unlike Mr. Martinez, I don't come out say to how much l liked Jackson's film and then launch into a litany of discrapancies between what I saw and what Tolkien's work is supposed to be. Nor do I soft-peddle or apologize for Mr. Jackson by saying that the changes were probably best for the making of a good adaptation to film.
What I'm saying is that Peter Jackson made a fine film which needs his previous film for reference and support. The previous movie was a fine adaptation of The Fellowship of the Ring. This latest one didn't suit me as it has most others and the point of divergence is when Jackson is clearly re-writing Tolkien's story in the second half. There is much in the first half of TTT that will please Tolkien fans who enjoyed the first film. In the second half, you have to take your Tolkien goggles off and accept that one man has decided to fill another's shoes if you wish to continue enjoying the film.
I could accept it to enjoy a good movie. But I can't accept that what we are watching from the middle half of TTT forward is a faithful adaptation of Tolkien's story. It's a story of Mr. Jackson's design that borrows the characters, creatures, and trappings of Mr. Tolkien's world. And I really don't see why he needed to do that.