I've been a member for about 8 years but never been offered one - probably because of my considerably un-centurion like spend pattern. It would have been useful today though - I had a big whinge when trying to book 2 nights for 1 at the Jumeirah Essex House in NY. No availability for my selected dates - which when I pushed back on is because they only allocate one room to the offer at any one time.
Someone is feeding you a line H99 - I've had multiple rooms allocated at the same time at a Jumeirah property (London and NY) on multiple occasions.
Just noticed that Expedia is cheaper for NY Jumeirah than Jumeirah direct for dates I need in Nov
The RM is a useful benefit, esp with the direct phone number. I find it a lot easier to communicate with mine via e-mail as it suits my daily work and meeting pattern.