True.
But why should the game expect the player to start over again in Vault Hunter Mode, and then move on to the DLC?
Seems like extra work to get it balanced with your character.
I think it's because if they let it scale from Level 30 to 50 in Normal mode, the DLC would be unbalanced with the maingame in normal mode...
Let's say you where Level 30 after finishing mainquest of maingame, in normal mode... Pandora scale to about Level 30 in normal mode, then you fast traveled to Oasis, which scaled way past Level 30... Okay.. fine, except for that when you where finished in Oasis and fast traveled back to the maingame, your character would be totally overkill when compared to the world outside of Oasis.
So I understand why they did this..
I don't know how many levels you can gain inside Oasis.. But let's say 5 levels.. Then you would be fine if you entered Oasis at Level 25 normal mode. If you're Level 30 + and finished killing The Warrior, the best way is to just start in TVHM and then fast travel to Oasis. As I've said, when you start a new game in TVHM, you can fast travel from Claptrap's hideout, in the very beginning of the game. So no problem..