However, over the last few weeks, I've read and heard from a bunch of people that should know (a few rangers/guides and one OT guide book) that they're actually Cabbage Gums (Euc. pauciflora).
Now, according to my EucaFlip (the widely acknowledged authority on all things Tree), Cabbage Gums grow to 20m between 200-700m altitude, and have white/silver bark streaked with red/brown. The examples I've seen have been between 700-800m (close) and closer to 40m high. Bark has been silver/white with no trace of red or brown.
Here's great example just as you start to reach the button-grass before the swing bridge.

Thoughts?