I don't know of many properties that doesn't charge more for double occupancy. So much so that I do not know how to invoke the 2nd guest stays free rule. Can you get Diamond benefits for 2 on a one adult room rate? Have any of you guys tried invoking this rule and getting full benefits??
The question is not if there is such a rule but more of whether the front desk staff knows of such a rule. I reckon it would be much hassle if you had to argue with the front desk staff on whether there is such a rule. The difference is about 15 US dollars a day so IMO it might not be worth the potiental problems you might encounter.