No one has ever (EVER) played a LOTR without multiball progression, the main reason being every single multiball was written with that in mind from day 1.
Now, there are points where it may not SEEM like there is... For ROTK, you must complete an entire level (4 jackpots) for it to remember you advanced a level. For TTT, if you get even just one super jackpot, you'll start over at the beginning again (although your jackpots will be higher the 2nd time through, starting at 150K instead of 100K).
But even in-house, during development, there was always progression. This is not debatable in any way.