No, what I was getting at is that what motivates this kind of decision from studios these days isn't "how to grab more money", it's far more their fears a movie might flop. So to me this smells a lot like a case of "but... isn't the movie too long and isn't this risky?" or "wouldn't three be more optimal?" than "let's milk it by forcing Jackson to make three". If they wanted three movies, they would have brought this up at the script stage, not during postproduction when doing this cost them.

You should see how often the studios recall trailers for revision or switch release dates (far more frequently than the public knows. Changes of mind after a trailer has been released are just the tip of the iceberg). They very rarely did that a few years ago, let alone recall movies which are presently at the foreign dubbing stage (which remains rare, but a few years ago it was basically unknown).