Is "Default" Needed?

I'm finally getting the hang of Bukkit, but there's just one question that's nagging me: do we need a "default" group in the file with all our other groups? This is my tracks.yml file:

tracks:
Admin:
groups:
- Newcomer
- Villager
- Hero
- Moderator
- Admin
worlds:
- world
- world_nether
promote-message: You have been promoted to administrator!
demote-message: Not so fast
Moderator:
groups:
- Newcomer
- Villager
- Hero
- Moderator
worlds:
- world
- world_nether
promote-message: You have been promoted to moderator!
demote-message: Ah, ah, ah . . .
Hero:
groups:
- Newcomer
- Villager
- Hero
worlds:
- world
- world_nether
promote-message: The village commends you. You are now a hero.
demote-message: Bad boy!
Villager:
groups:
- Newcomer
- Villager
worlds:
- world
- world_nether
promote-message: You have been registered. Welcome to the town.
Newcomer:
groups:
- Newcomer
worlds:
- world
promote-message: %name% has joined the server for the first time!

If this helps, would I need default anywhere in there?

 

You do not.

 

Alright, awesome.