Sirius and Gringotts

[potioncat]

No: HPFGUIDX 96206

x> Carol:
> I think it's a lot simpler. Admittedly, the Gringotts goblins go to
> great lengths to protect their gold and other valuables--dragons and
> spells and whatnot--but the protections are to prevent it from 
getting
> into the hands of anyone other than the rightful owner, even a
> fugitive from Azkaban. All they needed to take gold from the vault 
was
> Sirius's signature (I'm sure they examined it carefully to determine
> that it wasn't a forgery) and the key to the vault, which 
Crookshanks
> presumably had in an envelope along with the signed request for the 
gold.
> 

Potioncat:
Here's a thought I've wondered about.  If Serius could get gold out 
of Gringotts with just his signature, why didn't he get it out while 
he was in the tropics?  When Harry sees him again, (GoF) he's still 
wearing the robes from Azkaban.