Hilton HHonors - What To Use Diamond Desk For

From my limited experience as a Diamond and from reading here on FT, it seems that there are some things that the Diamond Desk does a really great job taking care of and there are other things that they're just not able/empowered to do. I thought it might be good to create and maintain a list for reference.

What To Use Diamond Desk For:

Diamond Force (http://www.flyertalk.com/forum/hilton-hhonors/514486-diamond-guaranteed-reservation-force-now-available-online.html) - Getting a paid or award stay (http://www.flyertalk.com/forum/hilton-hhonors/762794-reward-stay-diamond-special-arrangement.html) for a sold out night (excluding exceptional demand).
Requesting Upgrades (http://www.flyertalk.com/forum/hilton-hhonors/993854-what-use-diamond-desk.html#post12363118) - Any more feedback on the effectiveness of this?


What NOT To Use Diamond Desk For:

Best Rate Guarantee (http://www.flyertalk.com/forum/hilton-hhonors/508641-hilton-best-rate-guarantee-definitive-thread.html) - This is handled by corporate and there's nothing the Diamond Desk can do.


I know that many things will be YMMV, and that once in a while you'll run across a bad agent who won't help or a really good agent who can get something done that you normally can't do. I'm not interested in these types of exceptions, just what's typical.

What do you have to add? (I'll keep this initial post updated.)

When I book through DD I always ask them to write a note on the booking with a request for upgrade. Although it may be all in my head--I feel that I receive upgrades more routinely this way.