As the "secret" spread on the internet and more, and more people started to fax the resorts, several of the resorts have put a halt to it as they've been swamped with faxes. The rule of thumb now is to call and have your request added to your reservation. The room assigners see these comments on your reservation, just like the faxes, and it's a lot easier for them than trying to match up faxes with reservations. If you're concerned about CRO getting it right, call back and check. There is a longer lead-time for requests attached to reservations, I think it needs to be at least 10 days before check-in.