I'm a huge fan of fastpass, but I have to agree that it's not needed here - done properly, an Omnimover shouldn't need it as it should be continuously loading.
It's also why (and I've been criticized for saying this before) I dearly hope there are no "stop and wait" pre-shows in TLM. I want a wonderfully detailed queue, but with an Omnimover it's just a bad design decision.
I wouldn't trade in the classic HM pre-show for the world now, but it is true that it mucks up the works and reduces ride capacity, even under the best of circumstances (both rooms running, for example).