Removing the STS is a little bit drastic :-). You have it for a reason (SSO, federation, etc). You have a few options: decrease the expiration time of the token to a reasonable value for the volatility of your changes (8 hours might be excessive), or move the sensitive authorization information (e.g. privileges) to the app so it is checked each time.
You can do "claims enrichment" at the app level (through a custom AuhtenticationManager
in WIF) and still use claims model from your app code.
Technically there's no synching between the app and the STS. The Token is a snapshot of user attributes at the time of issuance and valid until it expires.